* src/tgba/state.hh (state_ptr_less_than::operator()): Make it const.
* src/tgba/tgbaproduct.cc: Include string.hh.
* src/ltlast/multop.hh (multop::add, multop::add_sorted): Do
not use qualified names in declarations.
* m4/gccwarn.m4 (CF_GXX_WARNINGS): Fix GXX test.
* src/ltlenv/defaultenv.hh, src/ltlenv/defaultenv.cc,
src/ltlenv/environment.hh: Add virtual destructors.
explicitely requested (--with-included-buddy) or if there is
now stuitable version already installed.
* buddy/: New directory. Contains a patched version of BuDDy 2.2.
* m4/buddy.m4: Make sure the installed BuDDy supports bdd_mergepairs.
Honor --with-included-buddy and --without-included-buddy. Define
the BUDDY_LDFLAGS and BUDDY_CPPFLAGS output variables, and the
WITH_INCLUDED_BUDDY Automake conditional
* Makefile.am [WITH_INCLUDED_BUDDY] (MAYBE_SUBDIRS): New variable.
(SUBDIRS): Prepend $(MAYBE_SUBDIRS).
* src/Makefile.am (libspot_LDFLAGS): New variable.
* src/tgba/Makefile.am (AM_CPPFLAGS): Add $(BUDDY_CPPFLAGS).
* src/tgbaalgos/Makefile.am (AM_CPPFLAGS): Likewise.
* src/tgbatest/Makefile.am (AM_CPPFLAGS): Likewise.
