These now become twa_run::reduce, twa_run::replay, and
twa_run::as_twa.

* src/twaalgos/reducerun.cc, src/twaalgos/reducerun.hh,
src/twaalgos/replayrun.cc, src/twaalgos/replayrun.hh: Delete.
* src/twaalgos/Makefile.am: Adjust.
* src/twaalgos/emptiness.cc, src/twaalgos/emptiness.hh: Move
the above functions here, as method of twa_run.
* src/bin/common_aoutput.hh, src/bin/ltlcross.cc,
src/tests/emptchk.cc, src/tests/ikwiad.cc, src/tests/randtgba.cc,
wrap/python/ajax/spotcgi.in, iface/ltsmin/modelcheck.cc: Adjust.
* NEWS: List the renamings.