XFA::language_contains: Collapse epsilon chains
Revert "XFA containment generalization: build KeyedSemElemSets"

This reverts commit b3d9b5a4dfc30cf981443f67cc8bbd00b855d64f.

Conflicts:
	AddOns/Xfa/Source/wali/xfa/Xfa.cpp
Fixes for compiler errors one back
Re do the collapseEpsilonEdges transformation from a moment ago
Add BDD stat function