* src/ltlvisit/destroy.cc, src/ltlvisit/destroy.hh,
src/ltlvisit/reduce.cc, src/ltlvisit/reduce.hh: Delete.
* src/ltlvisit/Makefile.am: Adjust.
* src/ltlvisit/clone.cc, src/ltlvisit/clone.hh (clone): Remove.
* src/ltlvisit/contain.hh (reduce_tau03): Remove.