Rework the way we compute and use cut-points to catch more patterns we
can rewrite. Also Use BDDs to check if a Boolean sub-expression is
false or true. Fixes issue #540.
* spot/tl/relabel.hh: Update documentation
* spot/tl/relabel.cc (relabel_bse): Rework.
* tests/core/ltlfilt.test: Add more test cases.
* tests/python/_mealy.ipynb: Update.
* NEWS: Mention the change.