* spot/twaalgos/cleanacc.cc (simplify_acceptance_here): Run the
simplifications in a loop until the condition does not change anymore.
* tests/python/simplacc.py, tests/core/accsimpl.test,
tests/core/remfin.test, tests/python/merge.py,
tests/python/simplacc.py, tests/python/toparity.py: Update expected
results.
* tests/python/automata.ipynb: Update the failing example to a more
interesting one, matching the one in doc/org/autfilt.org.
* spot/twaalgos/cleanacc.cc: Use cleanup_acceptance if
propagate_fin_inf was useful.
* spot/twa/acc.hh: Avoid to reverse the order of the condition in
propagate_fin_inf.
* tests/core/accsimpl.test, tests/core/remfin.test,
tests/python/merge.py, tests/python/automata.ipynb: Update tests.
* tests/python/toparity.py: Update tests and add tests to check the
number of states.
Fixes#315.
* spot/twaalgos/cleanacc.cc (simplify_acceptance_here): Do not
compare the first edge against previous_a.
* tests/core/accsimpl.test: New file.
* tests/Makefile.am: Add it.
* NEWS: Mention the bug.