Fix part of issue #371 and add test.
Kill Threading's copy of ReferenceComparer
Fix List.Enumerator not being a struct
Stop using Debug.WriteLine because it !@%*(!@%*ing blocks for no reason

Conflicts:

	JSIL/Transforms/StaticAnalysis/EmulateStructAssignment.cs
Fix reference writes not cloning structs
Fix issue #466
Fix issue #395.
Fix BinaryTrees choking on new invocation ThisReference copy semantics
Correctness fixes
Remove implicit bool conversion
Merge

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extra : amend_source : 791eec21785798ea0498d9b5ae981488d6ac7a01