* iface/dve2/dve2.cc, src/kripke/kripkeexplicit.cc,
src/kripke/kripkeexplicit.hh, src/ta/tgtaexplicit.cc,
src/ta/tgtaexplicit.hh, src/ta/tgtaproduct.cc, src/ta/tgtaproduct.hh,
src/tgba/taatgba.cc, src/tgba/taatgba.hh, src/tgba/tgba.hh,
src/tgba/tgbabddconcrete.cc, src/tgba/tgbabddconcrete.hh,
src/tgba/tgbaexplicit.hh, src/tgba/tgbakvcomplement.cc,
src/tgba/tgbakvcomplement.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/tgbascc.cc, src/tgba/tgbascc.hh, src/tgba/tgbasgba.cc,
src/tgba/tgbasgba.hh, src/tgba/tgbatba.cc, src/tgba/tgbatba.hh,
src/tgba/tgbaunion.cc, src/tgba/tgbaunion.hh, src/tgba/wdbacomp.cc:
Here.
* NEWS: Mention it.

* src/kripke/fairkripke.cc, src/kripke/fairkripke.hh,
src/ta/tgtaexplicit.cc, src/ta/tgtaexplicit.hh, src/tgba/taatgba.cc,
src/tgba/taatgba.hh, src/tgba/tgba.cc, src/tgba/tgba.hh,
src/tgba/tgbabddconcrete.cc, src/tgba/tgbabddconcrete.hh,
src/tgba/tgbaexplicit.hh, src/tgba/tgbakvcomplement.cc,
src/tgba/tgbakvcomplement.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/tgbascc.cc, src/tgba/tgbascc.hh, src/tgba/tgbasgba.cc,
src/tgba/tgbasgba.hh, src/tgba/tgbatba.cc, src/tgba/tgbatba.hh,
src/tgba/tgbaunion.cc, src/tgba/tgbaunion.hh, src/tgba/wdbacomp.cc:
Remove anything related to support_variables() and
compute_support_variables().
* NEWS: Mention it.
* src/tgbaalgos/powerset.cc: Adjust the computation of all possible
conditions.

nsheap was an horror full of virtual functions required to
customize gtec to implement inclusion-based emptiness-check
in GreatSPN support.  Since this support has been removed, we
can remove the nsheap cruft as well.  Note that nsheap was
also used in emptinessta for no good reason (the code from
emptinessta was simply copied from gtec without cleanup).

* src/tgbaalgos/gtec/nsheap.cc, src/tgbaalgos/gtec/nsheap.hh:
Delete.
* src/tgbaalgos/gtec/Makefile.am: Adjust.
* src/taalgos/emptinessta.cc, src/taalgos/emptinessta.hh,
src/taalgos/tgba2ta.cc, src/tgbaalgos/gtec/ce.cc,
src/tgbaalgos/gtec/gtec.cc, src/tgbaalgos/gtec/gtec.hh,
src/tgbaalgos/gtec/status.cc, src/tgbaalgos/gtec/status.hh:
Use a simple unordered_map.

It hasn't been tested for several year, may not even compile, has
to be linked with source code that isn't even publicly available,
and its presence was the only reason to keep some inefficient
code in gtec.cc and friends.

* iface/gspn/: Delete this directory.
* iface/Makefile.am, configure.ac, README: Adjust.
* m4/gspnlib.m4: Delete.
* src/sanity/Makefile.am: Do not use LIBGSPN_CPPFLAGS.

* src/tgbaalgos/simulation.cc: Here.

* src/sanity/style.test: Add a test.
* iface/dve2/dve2.cc, iface/dve2/dve2check.cc, src/bin/common_output.cc,
src/bin/dstar2tgba.cc, src/bin/ltl2tgba.cc, src/bin/ltlcross.cc,
src/dstarparse/dra2ba.cc, src/dstarparse/fmterror.cc,
src/dstarparse/nsa2tgba.cc, src/kripke/kripkeprint.cc,
src/kripkeparse/fmterror.cc, src/ltlast/atomic_prop.cc,
src/ltlast/bunop.cc, src/ltltest/ltlrel.cc, src/ltltest/reduc.cc,
src/ltltest/syntimpl.cc, src/ltlvisit/dotty.cc, src/ltlvisit/lbt.cc,
src/ltlvisit/randomltl.cc, src/ltlvisit/relabel.cc,
src/ltlvisit/simplify.cc, src/ltlvisit/tostring.cc, src/misc/bitvect.cc,
src/misc/optionmap.cc, src/misc/timer.cc, src/neverparse/fmterror.cc,
src/priv/freelist.cc, src/saba/sabacomplementtgba.cc,
src/sabaalgos/sabadotty.cc, src/taalgos/dotty.cc,
src/taalgos/minimize.cc, src/tgba/bdddict.cc, src/tgba/bddprint.cc,
src/tgba/futurecondcol.cc, src/tgba/taatgba.hh,
src/tgba/tgbakvcomplement.cc, src/tgba/tgbasafracomplement.cc,
src/tgbaalgos/compsusp.cc, src/tgbaalgos/cycles.cc,
src/tgbaalgos/dotty.cc, src/tgbaalgos/dtbasat.cc,
src/tgbaalgos/dtgbasat.cc, src/tgbaalgos/emptiness.cc,
src/tgbaalgos/gtec/gtec.cc, src/tgbaalgos/gv04.cc,
src/tgbaalgos/lbtt.cc, src/tgbaalgos/ltl2tgba_fm.cc,
src/tgbaalgos/minimize.cc, src/tgbaalgos/neverclaim.cc,
src/tgbaalgos/powerset.cc, src/tgbaalgos/replayrun.cc,
src/tgbaalgos/save.cc, src/tgbaalgos/scc.cc, src/tgbaalgos/sccfilter.cc,
src/tgbaalgos/weight.cc, src/tgbaalgos/word.cc,
src/tgbaparse/fmterror.cc, src/tgbatest/bitvect.cc,
src/tgbatest/complementation.cc, src/tgbatest/intvcmp2.cc,
src/tgbatest/intvcomp.cc, src/tgbatest/ltl2tgba.cc,
src/tgbatest/randtgba.cc: Replace << "c" by << 'c' when
appropriate.

This of course concerns push_back and push_front as well.

* src/bin/common_finput.cc, src/bin/dstar2tgba.cc, src/bin/ltl2tgba.cc,
src/bin/ltl2tgta.cc, src/bin/ltlcross.cc, src/bin/ltlfilt.cc,
src/dstarparse/dstarparse.yy, src/kripkeparse/kripkeparse.yy,
src/ltlast/formula.cc, src/ltlparse/ltlparse.yy, src/misc/minato.cc,
src/neverparse/neverclaimparse.yy, src/priv/bddalloc.cc, src/ta/ta.cc,
src/taalgos/emptinessta.cc, src/tgba/taatgba.cc,
src/tgbaalgos/gtec/gtec.cc, src/tgbaalgos/gtec/sccstack.cc,
src/tgbaalgos/magic.cc, src/tgbaalgos/ndfs_result.hxx,
src/tgbaalgos/rundotdec.cc, src/tgbaalgos/scc.cc, src/tgbaalgos/se05.cc,
src/tgbaalgos/simulation.cc, src/tgbaalgos/tau03.cc,
src/tgbaalgos/tau03opt.cc, src/tgbaparse/tgbaparse.yy: Use emplace
to make the code less verbose and avoid creating temporaries.

* src/ltlvisit/simplify.cc, src/tgbaalgos/replayrun.cc: Here.

* src/tgbaalgos/bfssteps.cc, src/tgbaalgos/complete.cc,
src/tgbaalgos/cycles.cc, src/tgbaalgos/dtgbacomp.cc,
src/tgbaalgos/gtec/gtec.cc, src/tgbaalgos/gv04.cc,
src/tgbaalgos/isweakscc.cc, src/tgbaalgos/lbtt.cc,
src/tgbaalgos/neverclaim.cc, src/tgbaalgos/reachiter.cc,
src/tgbaalgos/replayrun.cc, src/tgbaalgos/safety.cc,
src/tgbaalgos/save.cc: Avoid calls to done().

The returned Boolean indicates whether there is a successor or not.
This way

|  for (i->first(); !i->done(); i->next())
|    {
|       ...
|    }

can be replaced by

| if (i->first()) do
|   {
|      ...
|   }
| while (i->next());

avoiding all the virtual calls to done().

* iface/dve2/dve2.cc, src/kripke/kripkeexplicit.cc,
src/kripke/kripkeexplicit.hh, src/ta/ta.hh, src/ta/taexplicit.cc,
src/ta/taexplicit.hh, src/ta/taproduct.cc, src/ta/taproduct.hh,
src/ta/tgtaproduct.cc, src/ta/tgtaproduct.hh, src/tgba/succiter.hh,
src/tgba/succiterconcrete.cc, src/tgba/succiterconcrete.hh,
src/tgba/taatgba.cc, src/tgba/taatgba.hh, src/tgba/tgba.hh,
src/tgba/tgbaexplicit.hh, src/tgba/tgbakvcomplement.cc,
src/tgba/tgbamask.cc, src/tgba/tgbaproduct.cc,
src/tgba/tgbasafracomplement.cc, src/tgba/tgbasgba.cc,
src/tgba/tgbatba.cc, src/tgba/tgbaunion.cc, src/tgba/tgbaunion.hh,
src/tgba/wdbacomp.cc: Implement and adjust to this new interface.

Instead of "delete iter;" we now do "aut->release_iter(iter);" to
give the iterator back to the automaton.  The TGBA classes now
reuse a previously returned tgba_succ_iterator to answer a succ_iter()
call, therefore avoiding (1) memory allocation, as well as (2) vtable
and other constant member initialization.

* src/tgba/tgba.hh, src/tgba/tgba.cc (release_iter, iter_cache_):
Implement a release_iter() that stores the released iterator
in iter_cache_.
* src/tgba/succiter.hh (internal::succ_iterable): Move...
* src/tgba/tgba.hh (tgba::succ_iterable): ... here. And use
release_iter().

* iface/dve2/dve2.cc, src/kripke/kripke.cc, src/kripke/kripke.hh,
src/tgba/succiterconcrete.cc, src/tgba/succiterconcrete.hh,
src/tgba/taatgba.hh, src/tgba/tgbabddconcrete.cc,
src/tgba/tgbaexplicit.hh, src/tgba/tgbamask.cc, src/tgba/tgbaproduct.cc,
src/tgba/tgbaproxy.cc, src/tgba/tgbascc.cc, src/tgba/tgbatba.cc,
src/tgba/tgbaunion.cc, src/tgba/tgbaunion.hh, src/tgba/wdbacomp.cc,
src/tgbaalgos/bfssteps.cc, src/tgbaalgos/compsusp.cc,
src/tgbaalgos/cycles.cc, src/tgbaalgos/dtbasat.cc,
src/tgbaalgos/dtgbasat.cc, src/tgbaalgos/gtec/gtec.cc,
src/tgbaalgos/gv04.cc, src/tgbaalgos/isweakscc.cc,
src/tgbaalgos/lbtt.cc, src/tgbaalgos/ltl2tgba_fm.cc,
src/tgbaalgos/magic.cc, src/tgbaalgos/ndfs_result.hxx,
src/tgbaalgos/neverclaim.cc, src/tgbaalgos/reachiter.cc,
src/tgbaalgos/replayrun.cc, src/tgbaalgos/safety.cc,
src/tgbaalgos/scc.cc, src/tgbaalgos/se05.cc,
src/tgbaalgos/simulation.cc, src/tgbaalgos/tau03.cc,
src/tgbaalgos/tau03opt.cc: Use release_iter() instead of deleting
iterators, and used recycle iter_cache_ in implementations of
tgba::succ_iter().

| tgba_succ_iterator* i = aut->succ_iter(s);
| for (i->begin(); !i->done(); i->next())
|   {
|      // ...
|   }
| delete i;

becomes

| for (auto i: aut->succ(s))
|   {
|      // ...
|   }

hiding the begin()/done()/next() interface, taking care of the delete,
and allowing more optimization to come.

* src/tgba/succiter.hh, src/tgba/tgba.hh: Implement the above
new interface.
* iface/gspn/ssp.cc, src/dstarparse/nsa2tgba.cc,
src/saba/sabacomplementtgba.cc, src/tgba/tgbakvcomplement.cc,
src/tgba/tgbamask.cc, src/tgba/tgbasafracomplement.cc,
src/tgba/tgbatba.cc, src/tgbaalgos/compsusp.cc, src/tgbaalgos/cutscc.cc,
src/tgbaalgos/degen.cc, src/tgbaalgos/emptiness.cc,
src/tgbaalgos/isdet.cc, src/tgbaalgos/ltl2tgba_fm.cc,
src/tgbaalgos/minimize.cc, src/tgbaalgos/powerset.cc,
src/tgbaalgos/safety.cc, src/tgbaalgos/simulation.cc,
src/tgbaalgos/tau03.cc, src/tgbatest/explicit2.cc: Update for
loops.

* src/tgbaalgos/degen.cc (unicity_table): Move and rename as...
* src/tgba/state.hh (state_unicity_table): ... this.
* src/tgbaalgos/cutscc.cc, src/tgbaalgos/cycles.cc,
src/tgbaalgos/cycles.hh, src/tgbaalgos/minimize.cc,
src/tgbaalgos/powerset.cc, src/tgbaalgos/powerset.hh,
src/tgbaalgos/safety.cc: Use it to simplify existing code.

* configure.ac: Enable C++11 mode.
* src/bdd.h: Use noexport, and add a move constructor and
move assignment operator.  The move version of these method
do not have to increment the reference counter, saving time.
On a small test run, this change saved 24% of the calls to
bdd_addref_nc().

* src/ltlast/atomic_prop.cc, src/ltlast/atomic_prop.hh,
src/ltlast/automatop.cc, src/ltlast/automatop.hh, src/ltlast/binop.cc,
src/ltlast/binop.hh, src/ltlast/bunop.cc, src/ltlast/bunop.hh,
src/ltlast/multop.cc, src/ltlast/multop.hh, src/ltlast/unop.cc,
src/ltlast/unop.hh: Use std::tuple to replace nested std::pair,
simplify calls to std::map::erase, use auto and std::make_pair with
insert, and simplify the dump() method using a range for.

* src/misc/random.cc, src/misc/random.hh (srand, drand, mrand, rrand,
barand): Simplify using <random> from C++11.
(nrand, bmrand, prand): Remove these unused functions.
* src/tgbaalgos/randomgraph.cc: Adjust the use of barand.
* configure.ac: Do not check for srand48 and drand48.

* README: Do not mention Boost.
* configure.ac: Do not check for Boost.
* m4/boost.m4: Delete.

The bitvect implementation seems a tad faster, but most importantly
this removes the last dependency on Boost.

* src/tgba/tgbasafracomplement.cc: Replace boost::dynamic_bitset by
spot::bitvect.

* src/misc/bitvect.hh: New method.
* src/tgbatest/bitvect.cc, src/tgbatest/bitvect.test: Test it.

* src/eltlparse/eltlparse.yy, src/ltlast/formula_tree.hh,
src/ltlast/nfa.hh, src/saba/sabastate.hh, src/tgba/state.hh: Here.

But do not replace it by std::unique_ptr, because this was not
really equivalent.

* src/misc/unique_ptr.hh: Delete.
* src/misc/Makefile.am: Adjust.
* src/tgbaalgos/simulation.cc, src/tgbatest/ltl2tgba.cc: Call
delete explicitly.

* configure.ac, m4/ax_check_compile_flag.m4: Update from
Vaucanson 2.  (Thank you Akim.)

* src/misc/common.hh: Conditionally define SPOT_DELETED to = delete.
* src/ltlvisit/simplify.hh, src/ta/taexplicit.hh, src/ta/taproduct.hh,
src/tgba/bdddict.hh, src/tgba/taatgba.hh, src/tgba/tgbabddconcrete.hh,
src/tgba/tgbaexplicit.hh, src/tgba/tgbaproduct.hh, src/tgba/tgbasgba.hh,
src/tgba/tgbatba.hh, src/tgba/tgbaunion.hh, src/tgba/wdbacomp.cc: Use
SPOT_DELETED.
* wrap/python/spot.i: Include common.hh.
* wrap/python/Makefile.am: Remove useless definition of SPOT_API
and BUDDY_API.

* src/ltlvisit/simplify.hh, src/ta/taexplicit.hh, src/ta/taproduct.hh,
src/tgba/bdddict.hh, src/tgba/taatgba.hh, src/tgba/tgbabddconcrete.hh,
src/tgba/tgbaexplicit.hh, src/tgba/tgbaproduct.hh, src/tgba/tgbasgba.hh,
src/tgba/tgbatba.hh, src/tgba/tgbaunion.hh, src/tgba/wdbacomp.cc: Here.

* src/bin/common_finput.cc, src/bin/genltl.cc, src/bin/ltlcross.cc,
src/bin/randltl.cc: Simplify.

* bench/scc-stats/stats.cc, bench/split-product/cutscc.cc,
iface/gspn/ssp.cc, src/bin/ltlcross.cc, src/bin/ltlfilt.cc,
src/bin/randltl.cc, src/dstarparse/nsa2tgba.cc, src/ltlast/formula.hh,
src/ltlast/nfa.hh, src/ltlvisit/contain.hh, src/ltlvisit/dotty.cc,
src/ltlvisit/mark.hh, src/ltlvisit/relabel.cc, src/ltlvisit/relabel.hh,
src/ltlvisit/simplify.cc, src/ltlvisit/snf.hh, src/misc/hash.hh,
src/misc/mspool.hh, src/priv/acccompl.hh, src/priv/accconv.hh,
src/saba/explicitstateconjunction.hh, src/saba/sabastate.hh,
src/sabaalgos/sabareachiter.hh, src/sanity/style.test,
src/ta/taexplicit.cc, src/ta/taexplicit.hh, src/taalgos/emptinessta.cc,
src/taalgos/minimize.cc, src/taalgos/reachiter.hh, src/tgba/state.hh,
src/tgba/taatgba.hh, src/tgba/tgbabddconcretefactory.hh,
src/tgba/tgbaexplicit.hh, src/tgba/tgbakvcomplement.cc,
src/tgba/tgbasafracomplement.cc, src/tgba/tgbatba.cc,
src/tgba/tgbatba.hh, src/tgbaalgos/cutscc.cc, src/tgbaalgos/cycles.hh,
src/tgbaalgos/degen.cc, src/tgbaalgos/dtbasat.cc,
src/tgbaalgos/dtgbasat.cc, src/tgbaalgos/eltl2tgba_lacim.cc,
src/tgbaalgos/emptiness.cc, src/tgbaalgos/gtec/explscc.hh,
src/tgbaalgos/gtec/nsheap.hh, src/tgbaalgos/gv04.cc,
src/tgbaalgos/ltl2tgba_fm.cc, src/tgbaalgos/magic.cc,
src/tgbaalgos/minimize.cc, src/tgbaalgos/ndfs_result.hxx,
src/tgbaalgos/powerset.hh, src/tgbaalgos/randomgraph.cc,
src/tgbaalgos/reachiter.hh, src/tgbaalgos/replayrun.cc,
src/tgbaalgos/safety.cc, src/tgbaalgos/scc.hh, src/tgbaalgos/se05.cc,
src/tgbaalgos/simulation.cc, src/tgbaalgos/tau03.cc,
src/tgbaalgos/tau03opt.cc: Adjust code.
* src/sanity/style.test: Remove check.

* m4/stl.m4: Delete.
* configure.ac: Do not check for unordered_map and friends.
* src/misc/hash.hh: Remove all conditional code.

* src/ltlast/atomic_prop.cc, src/ltlast/atomic_prop.hh,
src/ltlast/automatop.cc, src/ltlast/automatop.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: Move all
one-line accessors methods like nth(), child(), op()... from *.cc files
to their respective *.hh files.

* NEWS, configure.ac, doc/org/tools.org: Update version.