* spot/twaalgos/postproc.cc, spot/twaalgos/postproc.hh: Add support
for a colored option.
* bin/common_post.cc, bin/common_post.hh bin/autfilt.cc,
bin/ltl2tgba.cc, bin/dstar2tgba.cc: Add support for --colored-parity.
* bin/ltldo.cc: Adjust as well for consistency, even if --parity and
--colored-parity is not used here.
* tests/core/parity2.test: Add tests.
* doc/org/autfilt.org, doc/org/ltl2tgba.org: Add examples.
* NEWS: Mention --colored-parity.
* spot/twaalgos/postproc.hh, spot/twaalgos/postproc.cc: Add parity
options.
* bin/common_post.cc: Add support for --parity.
* NEWS: Mention it.
* tests/core/parity2.test: New file.
* tests/Makefile.am: Add it.
