(couvreur99_check_shy::couvreur99_check_shy): Add the group option,
and redefine todo as a list so it can be iterated over.
* src/tgbatest/ltl2tgba.cc, src/tgbatest/randtgba.cc: Introduce
couvreur99_shy- (for group=false) in addition to couvreur99_shy
(for group=true).
* iface/gspn/ssp.cc (couvreur99_check_ssp_shy_semi,
couvreur99_check_ssp_shy): Use group=true;