Factored out common traversal code
Use AstMapVisitor instead of ExprMapVisitor as needed
Merge branch 'master' into function

Conflicts:
	jkind-common/src/jkind/lustre/visitors/AstMapVisitor.java
	jkind-common/src/jkind/lustre/visitors/ExprMapVisitor.java
	jkind/src/jkind/translation/compound/FlattenCompoundComparisons.java
	jkind/src/jkind/translation/compound/FlattenCompoundExpressions.java
	jkind/src/jkind/translation/compound/FlattenCompoundVariables.java
	jkind/src/jkind/translation/compound/RemoveArrayUpdates.java
	jkind/src/jkind/translation/compound/RemoveNonConstantArrayIndices.java
	jkind/src/jkind/translation/compound/RemoveRecordUpdates.java
	jkind/src/jkind/translation/tuples/FlattenTupleComparisons.java
	jkind/src/jkind/translation/tuples/LiftTuples.java