* spot/twa/acc.cc, spot/twa/acc.hh: Here.
* spot/parseaut/parseaut.yy, spot/twa/acc.hh,
spot/twaalgos/gtec/gtec.cc, spot/twaalgos/hoa.cc,
spot/twaalgos/neverclaim.cc, spot/twaalgos/product.cc,
spot/twaalgos/remfin.cc, spot/twaalgos/strength.cc: Adjust.
* NEWS: Mention the changes.
* wrap/python/spot_impl.i: Bind acc_cond the printer.
* wrap/python/tests/acc_cond.ipynb: Add more examples.

* spot/twa/acc.hh, spot/twa/acc.cc: Here.  Also remove
some redundant functions.
* spot/parseaut/parseaut.yy, spot/priv/accmap.hh, spot/tests/acc.cc,
spot/tests/twagraph.cc, spot/twa/taatgba.hh, spot/twa/twaproduct.cc,
spot/twaalgos/dtwasat.cc, spot/twaalgos/hoa.cc, spot/twaalgos/lbtt.cc,
spot/twaalgos/ltl2tgba_fm.cc, spot/twaalgos/product.cc,
spot/twaalgos/remfin.cc, spot/twaalgos/simulation.cc,
spot/twaalgos/tau03opt.cc, spot/twaalgos/weight.cc,
spot/twaalgos/weight.hh: Adjust.
* NEWS: Mention the changes.

so that we can optimize it when no Fin are used

* spot/twa/acc.cc, spot/twa/acc.hh: Do it.
* spot/twaalgos/complete.cc, spot/twaalgos/strength.cc: Adjust.

* NEWS: Mention the change.
* src/: Rename as ...
* spot/: ... this, adjust all headers to include <spot/...> instead of
"...", and adjust all Makefile.am to search headers from the top-level
directory.
* HACKING: Add conventions about #include.
* spot/sanity/style.test: Add a few more grep to catch cases
that do not follow these conventions.
* .gitignore, Makefile.am, README, bench/stutter/Makefile.am,
bench/stutter/stutter_invariance_formulas.cc,
bench/stutter/stutter_invariance_randomgraph.cc, configure.ac,
debian/rules, doc/Doxyfile.in, doc/Makefile.am,
doc/org/.dir-locals.el.in, doc/org/g++wrap.in, doc/org/init.el.in,
doc/org/tut01.org, doc/org/tut02.org, doc/org/tut03.org,
doc/org/tut10.org, doc/org/tut20.org, doc/org/tut21.org,
doc/org/tut22.org, doc/org/tut30.org, iface/ltsmin/Makefile.am,
iface/ltsmin/kripke.test, iface/ltsmin/ltsmin.cc,
iface/ltsmin/ltsmin.hh, iface/ltsmin/modelcheck.cc,
wrap/python/Makefile.am, wrap/python/ajax/spotcgi.in,
wrap/python/spot_impl.i, wrap/python/tests/ltl2tgba.py,
wrap/python/tests/randgen.py, wrap/python/tests/run.in: Adjust.

False/True are problematic in Python, and I don't like that the
enum is op::False but the constructor formula::ff().  So let's
just use ff and tt everywhere, and also eword instead of EmptyWord.

* src/ltlast/formula.hh (False, True, EmptyWord, AP, is_false, is_true):
Rename to...
(ff, tt, eword, ap, is_ff, is_tt): ... these.
* iface/ltsmin/ltsmin.cc, src/ltlast/formula.cc,
src/ltlvisit/apcollect.cc, src/ltlvisit/dot.cc, src/ltlvisit/mark.cc,
src/ltlvisit/mutation.cc, src/ltlvisit/print.cc,
src/ltlvisit/relabel.cc, src/ltlvisit/simpfg.cc,
src/ltlvisit/simplify.cc, src/ltlvisit/snf.cc, src/ltlvisit/unabbrev.cc,
src/twa/acc.cc, src/twa/acc.hh, src/twa/formula2bdd.cc,
src/twaalgos/gtec/gtec.cc, src/twaalgos/hoa.cc, src/twaalgos/ltl2taa.cc,
src/twaalgos/ltl2tgba_fm.cc, src/twaalgos/neverclaim.cc,
src/twaalgos/product.cc, src/twaalgos/remfin.cc, src/twaalgos/safety.cc,
src/tests/parseerr.test, src/tests/utf8.test, wrap/python/spot.py:
Adjust.

Flatten the formula ltl::formula hiearchy into a single ltl::vnode that
has an enumerator to distinguish the types of node, and a common
interface to access children, update reference counts, etc.  The
ltl::formula class is now a thin wrapper around an ltl::vnode pointer to
keep track of reference counts automatically.  Visitor are not used
anymore; we now have map() and traversor() methods that are more
concise.

This basically fixes #43, but should be followed by some fine tuning
that should now be localized to the formula.hh and formula.cc files.

Some statistics about this patch.  I started working on it on Sep 9, had
a first compiling version two weeks later on Sep 22, and it then took 5
days to fixes the ~70 distincts bugs that were introduced during the
conversion.  About 13200 lines were modified, and one third of those
were removed.

* src/ltlast/formula.cc, src/ltlast/formula.hh: Complete rewrite,
including what was in separate nearby files.
* src/ltlast/allnodes.hh, src/ltlast/atomic_prop.cc,
src/ltlast/atomic_prop.hh, src/ltlast/binop.cc, src/ltlast/binop.hh,
src/ltlast/bunop.cc, src/ltlast/bunop.hh, src/ltlast/constant.cc,
src/ltlast/constant.hh, src/ltlast/multop.cc, src/ltlast/multop.hh,
src/ltlast/unop.cc, src/ltlast/unop.hh, src/ltlvisit/dump.cc,
src/ltlvisit/dump.hh, src/ltlast/predecl.hh: Delete these files.  Their
feature have been merged in formula.hh and formula.cc.
* src/ltlast/visitor.hh, src/ltlvisit/clone.cc, src/ltlvisit/clone.hh,
src/ltlvisit/dump.hh, src/ltlvisit/postfix.cc, src/ltlvisit/postfix.hh:
Delete these files, as we do not use visitors anymore.
* bench/stutter/stutter_invariance_formulas.cc,
bench/stutter/stutter_invariance_randomgraph.cc, doc/org/tut01.org,
doc/org/tut02.org, doc/org/tut10.org, doc/org/tut22.org,
iface/ltsmin/ltsmin.cc, iface/ltsmin/ltsmin.hh,
iface/ltsmin/modelcheck.cc, src/bin/autfilt.cc,
src/bin/common_aoutput.cc, src/bin/common_aoutput.hh,
src/bin/common_finput.cc, src/bin/common_finput.hh,
src/bin/common_output.cc, src/bin/common_output.hh,
src/bin/common_trans.cc, src/bin/common_trans.hh, src/bin/dstar2tgba.cc,
src/bin/genltl.cc, src/bin/ltl2tgba.cc, src/bin/ltl2tgta.cc,
src/bin/ltlcross.cc, src/bin/ltldo.cc, src/bin/ltlfilt.cc,
src/bin/ltlgrind.cc, src/bin/randaut.cc, src/bin/randltl.cc,
src/kripke/kripkeexplicit.cc, src/kripke/kripkeexplicit.hh,
src/kripkeparse/kripkeparse.yy, src/ltlast/Makefile.am,
src/ltlenv/declenv.cc, src/ltlenv/declenv.hh, src/ltlenv/defaultenv.cc,
src/ltlenv/defaultenv.hh, src/ltlenv/environment.hh,
src/ltlparse/ltlparse.yy, src/ltlparse/public.hh,
src/ltlvisit/Makefile.am, src/ltlvisit/apcollect.cc,
src/ltlvisit/apcollect.hh, src/ltlvisit/contain.cc,
src/ltlvisit/contain.hh, src/ltlvisit/dot.cc, src/ltlvisit/dot.hh,
src/ltlvisit/exclusive.cc, src/ltlvisit/exclusive.hh,
src/ltlvisit/length.cc, src/ltlvisit/length.hh, src/ltlvisit/mark.cc,
src/ltlvisit/mark.hh, src/ltlvisit/mutation.cc,
src/ltlvisit/mutation.hh, src/ltlvisit/nenoform.cc,
src/ltlvisit/nenoform.hh, src/ltlvisit/print.cc, src/ltlvisit/print.hh,
src/ltlvisit/randomltl.cc, src/ltlvisit/randomltl.hh,
src/ltlvisit/relabel.cc, src/ltlvisit/relabel.hh,
src/ltlvisit/remove_x.cc, src/ltlvisit/remove_x.hh,
src/ltlvisit/simpfg.cc, src/ltlvisit/simpfg.hh,
src/ltlvisit/simplify.cc, src/ltlvisit/simplify.hh, src/ltlvisit/snf.cc,
src/ltlvisit/snf.hh, src/ltlvisit/unabbrev.cc, src/ltlvisit/unabbrev.hh,
src/parseaut/parseaut.yy, src/ta/taexplicit.cc, src/ta/tgtaexplicit.cc,
src/taalgos/minimize.cc, src/taalgos/tgba2ta.cc, src/tests/bare.test,
src/tests/checkpsl.cc, src/tests/checkta.cc,
src/tests/complementation.cc, src/tests/consterm.cc,
src/tests/emptchk.cc, src/tests/equalsf.cc, src/tests/ikwiad.cc,
src/tests/isop.test, src/tests/kind.cc, src/tests/length.cc,
src/tests/ltldo.test, src/tests/ltlfilt.test, src/tests/ltlgrind.test,
src/tests/ltlprod.cc, src/tests/ltlrel.cc,
src/tests/parse_print_test.cc, src/tests/parseaut.test,
src/tests/parseerr.test, src/tests/randtgba.cc, src/tests/readltl.cc,
src/tests/reduc.cc, src/tests/syntimpl.cc, src/tests/taatgba.cc,
src/tests/tostring.cc, src/tests/twagraph.cc, src/tests/utf8.test,
src/twa/acc.cc, src/twa/bdddict.cc, src/twa/bdddict.hh,
src/twa/bddprint.cc, src/twa/formula2bdd.cc, src/twa/formula2bdd.hh,
src/twa/taatgba.cc, src/twa/taatgba.hh, src/twa/twa.cc, src/twa/twa.hh
src/twa/twagraph.cc, src/twa/twagraph.hh, src/twa/twasafracomplement.cc,
src/twaalgos/compsusp.cc, src/twaalgos/compsusp.hh,
src/twaalgos/dtgbasat.cc, src/twaalgos/hoa.cc, src/twaalgos/lbtt.cc,
src/twaalgos/ltl2taa.cc, src/twaalgos/ltl2taa.hh,
src/twaalgos/ltl2tgba_fm.cc, src/twaalgos/ltl2tgba_fm.hh,
src/twaalgos/minimize.cc, src/twaalgos/minimize.hh,
src/twaalgos/neverclaim.cc, src/twaalgos/postproc.cc,
src/twaalgos/postproc.hh, src/twaalgos/powerset.cc,
src/twaalgos/powerset.hh, src/twaalgos/randomgraph.cc,
src/twaalgos/remprop.cc, src/twaalgos/remprop.hh, src/twaalgos/stats.cc,
src/twaalgos/stats.hh, src/twaalgos/stutter.cc, src/twaalgos/stutter.hh,
src/twaalgos/translate.cc, src/twaalgos/translate.hh,
wrap/python/ajax/spotcgi.in, wrap/python/spot.py,
wrap/python/spot_impl.i, wrap/python/Makefile.am,
wrap/python/tests/automata-io.ipynb, wrap/python/tests/formulas.ipynb,
wrap/python/tests/ltl2tgba.py, wrap/python/tests/ltlparse.py,
wrap/python/tests/ltlsimple.py, wrap/python/tests/randltl.ipynb: Adjust
to use the new interface.
* src/sanity/style.test: Accept more C++11 patterns.
* NEWS: Mention the change.

Fixes #99.

* src/tests/parseaut.test: New test case.
* src/twa/acc.cc (is_generalized_rabin): Fix detection
of Fin(0)|Fin(1)|Fin(2)&Inf(3).
* NEWS: Mention it.

* src/bin/randaut.cc: Replace the --acc-type and --acc-sets
options by a more general --acceptance option, that take either
an acceptance formula, or an acceptance name parametred by ranges.
Also accept a range for the number of atomic propositions.
* src/twaalgos/randomgraph.cc (random_acceptance): Move...
* src/twa/acc.cc, src/twa/acc.hh (random): ... here.
(parse_acc_code): Generalize to accept ranges instead of
numbers whenever sensible, and accept a 'random' acceptance.
* src/tests/randaut.test: Adjust tests and add more.
* wrap/python/tests/randaut.ipynb: Adjust call to randaut.

According to https://github.com/adl/hoaf/issues/46

* src/twa/acc.cc (parity): Adjust generation.
* src/tests/hoaparse.test, wrap/python/tests/accparse.ipynb:
Adjust existing test cases.
* wrap/python/tests/accparse2.py: New test cases.

* src/twa/acc.cc: Fix it.
* wrap/python/tests/accparse.ipynb: Adjust.

* src/twa/acc.cc: Allow duplicate and reordered pairs.  Also recognize
the single-pair cases.
* src/twaalgos/hoa.cc: When Rabin or Streett is detected, canonicalize
the Acceptance: line.
* src/tests/hoaparse.test, wrap/python/tests/accparse2.py: More tests.
* src/tests/sbacc.test: Adjust.

It has two modes: strict or not.  In strict mode (tested in
hoaparse.test), the acceptance formula has to match exactly the one
given in the HOA spec.  In non-strict mode (tested in accparse2.py)
any equivalent formula is accepted.

* src/twa/acc.cc, src/twa/acc.hh (acc_cond::is_parity): New method.
* src/twaalgos/hoa.cc: Use it.
* src/tests/hoaparse.test: Test it.
* wrap/python/spot_impl.i: Bind it.
* wrap/python/tests/accparse2.py: New file.
* wrap/python/tests/Makefile.am: Add it.

* src/twa/acc.cc, src/twa/acc.hh: Here.
* wrap/python/tests/accparse.ipynb: Test it.

So far the HOA output would emit an acc-name only
for generalized-Buchi or inferior types (Buchi, all).
It now knows about none, co-Buchi, generalized-co-Buchi,
Rabin, Streett, and generalized-Rabin as well.

* src/twa/acc.cc, src/twa/acc.hh: Add detection code.
* src/twaalgos/hoa.cc: Use it.
* src/tests/remfin.test, src/tests/maskacc.test,
src/tests/complete.test, src/tests/sim3.test,
src/tests/ltl2dstar.test: Adjust tests.
* src/tests/hoaparse.test: Adjust and add more tests.

* src/twa/acc.cc, src/twa/acc.hh: Add method to create
standard acceptance conditions, and adjust the parse_acc_code
to recognize them
* wrap/python/spot_impl.i (acc_cond::acc_code): Add a printer.
* wrap/python/tests/accparse.ipynb: New test file.
* wrap/python/tests/Makefile.am: Add it.
* src/tests/satmin2.test: Use the new syntax.

* src/twa/acc.cc: Here.
* src/tests/acc.test: Adjust.

This is still missing tests.

* src/bin/autfilt.cc: Add a --sat-minimize option.
* src/misc/optionmap.cc, src/misc/optionmap.hh: Allow passing strings.
* src/twa/acc.cc, src/twa/acc.hh: Add helper functions needed
by the SAT-encoder.
* src/twaalgos/complete.hh: Typos.
* src/twaalgos/dtbasat.hh: Adjust comment.
* src/twaalgos/dtgbasat.cc, src/twaalgos/dtgbasat.hh: Generalize
to take the target acceptance as input.
* src/twaalgos/postproc.cc, src/tests/ltl2tgba.cc: Adjust calls.
* src/twaalgos/sbacc.cc, src/twaalgos/sbacc.hh: Don't pass
the pointer by reference.
* src/tests/acc.cc, src/tests/acc.test: More tests
for the acceptance helper function.

as reported by cppcheck

* src/taalgos/emptinessta.cc, src/taalgos/tgba2ta.cc, src/twa/acc.cc,
src/twaalgos/minimize.cc, src/twaalgos/neverclaim.cc,
src/twaalgos/remprop.cc, src/twaalgos/sccinfo.cc: Here.

Automatic mass renaming.

* src/graphtest/tgbagraph.cc, src/tgba/acc.cc, src/tgba/acc.hh,
src/tgba/bdddict.cc, src/tgba/bdddict.hh, src/tgba/bddprint.cc,
src/tgba/bddprint.hh, src/tgba/formula2bdd.cc,
src/tgba/formula2bdd.hh, src/tgba/fwd.hh, src/tgba/Makefile.am,
src/tgba/taatgba.cc, src/tgba/taatgba.hh, src/tgba/tgba.cc,
src/tgba/tgbagraph.cc, src/tgba/tgbagraph.hh, src/tgba/tgba.hh,
src/tgba/tgbamask.cc, src/tgba/tgbamask.hh, src/tgba/tgbaproduct.cc,
src/tgba/tgbaproduct.hh, src/tgba/tgbaproxy.cc, src/tgba/tgbaproxy.hh,
src/tgba/tgbasafracomplement.cc, src/tgba/tgbasafracomplement.hh,
src/tgba/.cvsignore: Rename as...
* src/graphtest/twagraph.cc, src/twa/acc.cc, src/twa/acc.hh,
src/twa/bdddict.cc, src/twa/bdddict.hh, src/twa/bddprint.cc,
src/twa/bddprint.hh, src/twa/formula2bdd.cc, src/twa/formula2bdd.hh,
src/twa/fwd.hh, src/twa/Makefile.am, src/twa/taatgba.cc,
src/twa/taatgba.hh, src/twa/twa.cc, src/twa/twagraph.cc,
src/twa/twagraph.hh, src/twa/twa.hh, src/twa/twamask.cc,
src/twa/twamask.hh, src/twa/twaproduct.cc, src/twa/twaproduct.hh,
src/twa/twaproxy.cc, src/twa/twaproxy.hh,
src/twa/twasafracomplement.cc, src/twa/twasafracomplement.hh,
src/twa/.cvsignore: ... these.
* README, bench/stutter/stutter_invariance_randomgraph.cc,
configure.ac, iface/ltsmin/modelcheck.cc, src/Makefile.am,
src/bin/common_aoutput.cc, src/bin/common_conv.hh,
src/bin/common_trans.hh, src/bin/dstar2tgba.cc, src/bin/ltl2tgta.cc,
src/bin/randaut.cc, src/dstarparse/dra2ba.cc,
src/dstarparse/public.hh, src/graphtest/Makefile.am,
src/graphtest/ngraph.cc, src/hoaparse/hoaparse.yy,
src/hoaparse/public.hh, src/kripke/fairkripke.hh,
src/kripke/kripkeexplicit.cc, src/kripke/kripkeprint.cc,
src/kripkeparse/kripkeparse.yy, src/ltlvisit/apcollect.cc,
src/ltlvisit/apcollect.hh, src/ltlvisit/exclusive.hh,
src/ltlvisit/simplify.cc, src/ltlvisit/simplify.hh,
src/priv/accmap.hh, src/ta/ta.hh, src/ta/taexplicit.cc,
src/ta/taexplicit.hh, src/ta/tgta.hh, src/ta/tgtaexplicit.cc,
src/ta/tgtaexplicit.hh, src/ta/tgtaproduct.hh, src/taalgos/dotty.cc,
src/taalgos/emptinessta.cc, src/taalgos/minimize.cc,
src/taalgos/tgba2ta.cc, src/taalgos/tgba2ta.hh,
src/tgbaalgos/are_isomorphic.cc, src/tgbaalgos/are_isomorphic.hh,
src/tgbaalgos/bfssteps.cc, src/tgbaalgos/canonicalize.cc,
src/tgbaalgos/canonicalize.hh, src/tgbaalgos/cleanacc.hh,
src/tgbaalgos/complete.hh, src/tgbaalgos/compsusp.cc,
src/tgbaalgos/compsusp.hh, src/tgbaalgos/degen.cc,
src/tgbaalgos/degen.hh, src/tgbaalgos/dotty.cc,
src/tgbaalgos/dotty.hh, src/tgbaalgos/dtbasat.cc,
src/tgbaalgos/dtbasat.hh, src/tgbaalgos/dtgbacomp.hh,
src/tgbaalgos/dtgbasat.cc, src/tgbaalgos/dtgbasat.hh,
src/tgbaalgos/dupexp.cc, src/tgbaalgos/dupexp.hh,
src/tgbaalgos/emptiness.cc, src/tgbaalgos/emptiness.hh,
src/tgbaalgos/gtec/sccstack.hh, src/tgbaalgos/gtec/status.hh,
src/tgbaalgos/gv04.cc, src/tgbaalgos/gv04.hh, src/tgbaalgos/hoa.cc,
src/tgbaalgos/hoa.hh, src/tgbaalgos/isdet.hh, src/tgbaalgos/lbtt.cc,
src/tgbaalgos/lbtt.hh, src/tgbaalgos/ltl2taa.hh,
src/tgbaalgos/ltl2tgba_fm.cc, src/tgbaalgos/ltl2tgba_fm.hh,
src/tgbaalgos/magic.cc, src/tgbaalgos/magic.hh, src/tgbaalgos/mask.hh,
src/tgbaalgos/minimize.hh, src/tgbaalgos/ndfs_result.hxx,
src/tgbaalgos/neverclaim.cc, src/tgbaalgos/neverclaim.hh,
src/tgbaalgos/postproc.hh, src/tgbaalgos/powerset.cc,
src/tgbaalgos/powerset.hh, src/tgbaalgos/product.cc,
src/tgbaalgos/product.hh, src/tgbaalgos/projrun.cc,
src/tgbaalgos/projrun.hh, src/tgbaalgos/randomgraph.cc,
src/tgbaalgos/randomgraph.hh, src/tgbaalgos/randomize.hh,
src/tgbaalgos/reachiter.hh, src/tgbaalgos/reducerun.cc,
src/tgbaalgos/reducerun.hh, src/tgbaalgos/relabel.hh,
src/tgbaalgos/remfin.hh, src/tgbaalgos/remprop.hh,
src/tgbaalgos/replayrun.cc, src/tgbaalgos/replayrun.hh,
src/tgbaalgos/sbacc.hh, src/tgbaalgos/scc.cc, src/tgbaalgos/scc.hh,
src/tgbaalgos/sccfilter.hh, src/tgbaalgos/sccinfo.cc,
src/tgbaalgos/sccinfo.hh, src/tgbaalgos/se05.cc,
src/tgbaalgos/se05.hh, src/tgbaalgos/simulation.cc,
src/tgbaalgos/simulation.hh, src/tgbaalgos/stats.cc,
src/tgbaalgos/stats.hh, src/tgbaalgos/stripacc.hh,
src/tgbaalgos/stutter.cc, src/tgbaalgos/stutter.hh,
src/tgbaalgos/tau03.cc, src/tgbaalgos/tau03.hh,
src/tgbaalgos/tau03opt.cc, src/tgbaalgos/tau03opt.hh,
src/tgbaalgos/totgba.cc, src/tgbaalgos/totgba.hh,
src/tgbaalgos/weight.hh, src/tgbaalgos/word.cc, src/tgbatest/acc.cc,
src/tgbatest/complementation.cc, src/tgbatest/emptchk.cc,
src/tgbatest/ltl2tgba.cc, src/tgbatest/taatgba.cc,
wrap/python/spot_impl.i: Adjust.

* src/tgba/acc.cc, src/tgba/acc.hh (parse_acc_code): New function.
* src/tgbatest/acc.cc, src/tgbatest/acc.test: Test it.

* src/tgba/acc.cc, src/tgba/acc.hh: Add a way to extract
an unstatisfiable mark, and fix the eval() function for
Fin acceptance.
* src/tgbaalgos/complete.cc: Label the sink state using
an unsatisfiable mark.  Do not assume generalized Büchi.
* src/tgbatest/complete.test: New test.
* src/tgbatest/Makefile.am: Add it.

This implement several new options for --dot in order to
allow emptiness sets to be output as colored ⓿ or ❶...
Also add a SPOT_DOTDEFAULT environment variable.

* NEWS, src/bin/man/spot-x.x, src/bin/common_aoutput.cc,
src/bin/dstar2tgba.cc: Document the new options.
* doc/org/.dir-locals.el, doc/org/init.el.in: Setup
SPOT_DOTEXTRA and SPOT_DOTDEFAULT for all documents.
* doc/org/autfilt.org, doc/org/dstar2tgba.org, doc/org/ltl2tgba.org,
doc/org/ltldo.org, doc/org/oaut.org, doc/org/randaut.org,
doc/org/satmin.org: Adjust to this new setup.
* src/misc/escape.cc, src/misc/escape.hh (escape_html): New function.
* src/tgba/acc.cc, src/tgba/acc.hh (to_text, to_html): New method.
* src/tgbaalgos/dotty.cc: Implement the new options.
* src/tgbatest/readsave.test, wrap/python/tests/automata.ipynb: More
tests.
* wrap/python/spot.py: Make sure the default argument for
dotty_reachable is None, so that SPOT_DOTDEFAULT is honored.

* src/tgba/acc.cc, src/tgba/acc.hh (to_cnf, is_cnf): New functions.
* src/bin/autfilt.cc: Add a --cnf-acceptance option.
* src/tgbatest/acc2.test: Test it.

A Fin() terms with multiple sets should not appear under an And.

* src/tgba/acc.cc (is_dnf): Fix it.
* src/tgbatest/acc.cc, src/tgbatest/acc.test: Augment test case.

This way we have for instance
  (Inf(1) | Fin(2)) & (Fin(1) | Inf(3)) & Inf(0)
converted into just
  (Fin(1) & Fin(2) & Inf(0)) | (Inf(0)&Inf(1)&Inf(3))
while previously we would produce 4 terms:
  (Fin(2) & Fin(1) & Inf(0)) | (Fin(2) & (Inf(0)&Inf(3)))
  | (Fin(1) & (Inf(0)&Inf(1))) | (Inf(0)&Inf(1)&Inf(3))

* src/tgba/acc.cc (to_dnf): Recode it.
* src/tgbatest/acc2.test: Adjust.

Because scc_info does not perform a full emptiness check, it is not
always able to tell whether an SCC is accepting if the acceptance
condition use Fin primitives.  This introduce is_rejecting_scc() in
addition to to is_accepting_scc().  Only one of them may be true, but
they can both be false if scc_info has no idea whether the SCC is
accepting.

* src/tgbaalgos/sccinfo.cc, src/tgbaalgos/sccinfo.hh: Implement
is_rejecting_scc().
* src/bin/ltlcross.cc, src/tgba/acc.cc, src/tgba/acc.hh,
src/tgbaalgos/dtgbacomp.cc, src/tgbaalgos/isweakscc.cc,
src/tgbaalgos/remfin.cc, src/tgbaalgos/safety.cc,
src/tgbaalgos/sccfilter.cc: Use it.
* src/tgbaalgos/dotty.cc: Use is_rejecting_scc() and is_accepting_scc()
to color SCCs.
* doc/org/oaut.org: Document the colors used.
* src/tgbatest/neverclaimread.test, src/tgbatest/readsave.test: Adjust
tests.
* src/tgbatest/sccdot.test: New test case.
* src/tgbatest/Makefile.am: Add it.

* src/tgba/acc.cc: here.

* src/tgba/acc.cc, src/tgba/acc.hh: Move the strip() routine from
acc_cond into acc_cond::mark_t, and the strip() routine from
cleanacc.cc into acc_cond::acc_code.  Introduce helper functions
to create inf()/fin()/t()/f() at the acc_code level.
* src/tgbaalgos/cleanacc.cc: Simplify, using the strip() function
from acc_code.
* src/tgbaalgos/mask.cc (mask_acc_sets): Use the strip() function
from acc_code so that it work on non-Buchi acceptance.
* src/tgbatest/maskacc.test: Add a test for the latter change.
* src/tgbaalgos/sccfilter.cc, src/tgbatest/acc.cc: Adjust the
use mark_t::strip().

* src/bin/ltlcross.cc: Remove Fin-acceptance before
doing checks.  More --verbose output.
* src/tgba/acc.cc, src/tgba/acc.hh: Add an eval_sets() function
to find the set of acceptance sets needed to satisfy the condition
in an accepting SCC.
* src/tgbaalgos/gtec/ce.cc: Use eval_sets() when computing
a counter example.
* src/tgbaalgos/gtec/gtec.cc: Raise an exception when called
on an acceptance that contains Fin.
* src/tgbatest/ltl2dstar3.test, src/tgbatest/ltlcrossce2.test:
New files.
* src/tgbatest/Makefile.am: Add them.
* src/tgba/tgba.cc (is_empty): Call remove_fin if needed.
* src/tgbaalgos/product.cc, src/tgbaalgos/dtgbacomp.cc: Adjust
to work with generic acceptance.

* src/tgba/acc.cc, src/tgba/acc.hh (complement): New method.
* src/bin/autfilt.cc: Add a --complement-acceptance option.
* src/tgbatest/acc2.test: Test it.

* src/bin/autfilt.cc: Add remove_fin().
* src/tgba/acc.cc, src/tgba/acc.hh: Add is_dnf() and simplify eval().
* src/tgbaalgos/remfin.cc, src/tgbaalgos/remfin.hh: New files.
* src/tgbaalgos/Makefile.am: Add them.
* src/tgbatest/remfin.test: New file.
* src/tgbatest/Makefile.am: Add it.

* src/tgba/acc.cc, src/tgba/acc.hh: Implement a to_dnf()
method.
* src/bin/autfilt.cc: Add option --dnf-acceptance.
* src/tgbatest/acc2.test: Test it.

* src/tgba/acc.cc: Do not output (Inf(x)) or (Fin(x)).
* src/tgbatest/acc.test: Adjust.

* src/tgba/acc.hh: Add creation and printing of generic acceptance
code.
* src/tgba/acc.cc: New file.
* src/tgba/Makefile.am: Add it.
* src/tgbatest/acc.cc: More tests.
* src/tgbatest/acc.test: Update.
* src/tgba/tgba.hh (set_acceptance, get_acceptance): New methods.
* src/tgba/tgbagraph.hh: Store acceptance code.
* src/hoaparse/hoaparse.yy: Read any acceptance.
* src/dstarparse/nsa2tgba.cc, src/ta/taexplicit.cc,
src/tgba/tgbaproduct.cc, src/tgba/tgbasafracomplement.cc,
src/tgbaalgos/degen.cc, src/tgbaalgos/hoa.cc,
src/tgbaalgos/ltl2taa.cc, src/tgbaalgos/ltl2tgba_fm.cc,
src/tgbaalgos/product.cc, src/tgbaalgos/stutter.cc,
src/tgbatest/hoaparse.test: Adjust.