Reorganize this function so that syntactically there is only one
loop over the successors, and not two. Call reintroduce the call
to couvreur99_check_shy::state_index(), needed by SSP, and
suppress that to index_and_insert introduced on 2004-12-29. Also
split the "group" option in two: "group" and "group2". "group2"
is the equivalent of the older "group", while the new "group" is
weaker and faster.
(couvreur99_check_shy::state_index): Change prototype as needed by
the algorithm.
* src/tgbaalgos/gtec/gtec.hh: Adjust.
* src/tgbaalgos/gtec/nsheap.hh, src/tgbaalgos/gtec/nsheap.cc
(index_and_insert): Remove.
* iface/gspn/ssp.cc (couvreur99_check_shy_ssp::state_index): Adjust
to new prototype.
* bench/emptchk/README, bench/emptchk/algorithms: Adjust references
to group/group2.
(index_and_insert): New function.
* src/tgbaalgos/gtec/gtec.cc (couvreur99_check_shy::check): Rewrite.
(couvreur99_check_shy::clear_todo): New method.
* src/tgbaalgos/gtec/gtec.hh (couvreur99_check_shy::todo_item): New
struct.
* iface/gspn/ssp.cc (numbered_state_heap_ssp_semi::index_and_insert):
New method.
numbered_state_heap_hash_map_factory): New class.
* src/tgbaalgos/gtec/nsheap.cc (numbered_state_heap_hash_map_factory):
Implement it.
* src/tgbaalgos/gtec/gtec.hh (emptiness_check::emptiness_check,
emptiness_check_shy::emptiness_check_shy): Take a
numbered_state_heap_factory argument.
* tgbaalgos/gtec/status.hh
(emptiness_check_status::emptiness_check_status): Likewise.
(emptiness_check_status::h): Make it a numbered_state_heap*.
* src/tgbaalgos/gtec/ce.cc, tgbaalgos/gtec/gtec.cc,
tgbaalgos/gtec/status.cc: Adjust uses of ecs_->h.
