* src/ltlast/binop.hh, src/ltlast/binop.cc (EConcat, UConcat):
Add these new operators.
* src/ltlparse/ltlparse.yy, src/ltlparse/ltlscan.ll: Parse
these new operators.
* src/ltlvisit/simpfg.cc, src/ltlvisit/syntimpl.cc,
src/ltlvisit/tostring.cc, src/ltlvisit/basicreduce.cc,
src/ltlvisit/consterm.cc, src/ltlvisit/lunabbrev.cc,
src/ltlvisit/nenoform.cc, src/ltlvisit/reduce.cc
src/tgba/formula2bdd.cc, src/tgbaalgos/eltl2tgba_lacim.cc,
src/tgbaalgos/ltl2taa.cc, src/tgbaalgos/ltl2tgba_fm.cc,
src/tgbaalgos/ltl2tgba_lacim.cc: Add these new operators into the
switches.