Fixes#262 again. Reported by Maximilien Colange.
* spot/twaalgos/simulation.cc: Use state numbers to order classes, not
their signatures. The problem was that even if two simulation of the
same automaton assign the same signature, the BDD identifier used for
that signature might be different, and therefore the ordering obtained
by using BDDs as keys in a map can be different. A side-effect of
this change is that the order of states in automata produced by
simulation-based reduction may change; many tests had to be updated.
* tests/core/ltl2tgba.test: Add a new test case based on Maximilien's
report.
* tests/core/complement.test, tests/core/det.test,
tests/core/parseaut.test, tests/core/prodor.test,
tests/python/atva16-fig2a.ipynb, tests/python/automata.ipynb,
tests/python/decompose.ipynb, tests/python/highlighting.ipynb,
tests/python/piperead.ipynb, tests/python/testingaut.ipynb,
tests/python/word.ipynb: Update test cases for new order of states.
Related to #208.
* spot/twaalgos/dot.cc: Fix missing definitions of universal nodes,
and inclusion of universal nodes inside of SCC when none of the
destination comes back to the SCC.
* tests/python/_altscc.ipynb: Adjust and add more test cases.
* tests/core/alternating.test, tests/core/neverclaimread.test,
tests/core/readsave.test, tests/core/sccdot.test,
tests/python/decompose.ipynb: Adjust test cases.
* NEWS: Mention the bug.
