Fix bug: it's possible to leave an empty TransSet in WFA::kpmap; compensate for this
Fix dumbest bug ever: increment wrong iterator
Fix last(?) bug in WFA::RemoveStatesWithInDegree0:

If there are no transitions to a state, we'd never notice that it doesn't have any because it wouldn't be added to the predecessors' data structure. Fix that.
Remove debugging output
Fix test cases for collapseEpsilonChains, which now passes