spot::iar() was fixed to handle correctly Rabin-like conditions.
It also now supports Streett-like conditions.
* NEWS, spot/twaalgos/postproc.cc: document it
* spot/twaalgos/rabin2parity.cc, spot/twaalgos/rabin2parity.hh:
implement it
* tests/core/rabin2parity.test, tests/python/except.py: test it
* python/spot/impl.i: Add missing bindings from remprop.hh
* tests/python/except.py: New file to test several error cases.
* tests/Makefile.am: Add it.
* spot/twaalgos/rabin2parity.cc (iar): Fix error message.