* spot/twaalgos/toparity.cc: here
* spot/twa/acc.hh, spot/twa/acc.cc: compute symmetries of an acceptance
condition
* tests/python/accparse2.py, tests/python/toparity.py: test it
Fixes#271, reported by Henrich Lauko.
* spot/twa/acc.cc (maybe_accepting): Fix handling in case
of disjunction of Fin.
* tests/core/scc.test, tests/python/accparse2.py: Add more
tests.