Improve error message when resolving a generic TypeRef fails.
Stub out the System.Tuple types.
Declare the Console In/Out properties.
Statically assign sequential IDs to node types at startup.
Change VisitorCache's cache to a contiguous array (indexed by node type ID) instead of a dictionary.
Overhaul JSExpression.Get/SetValueNames to use Type IDs
Overhaul the JSNodeTraversalData cache to use Type IDs