simulation: do not depend on bdd numbers for ordering classes
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/core/scc.test, tests/python/atva16-fig2a.ipynb, tests/python/automata.ipynb, tests/python/decompose.ipynb, tests/python/decompose_scc.py, tests/python/highlighting.ipynb, tests/python/piperead.ipynb, tests/python/sccinfo.py, tests/python/simstate.py, tests/python/testingaut.ipynb, tests/python/word.ipynb: Update test case for new order of states.