Improve MatchingNode
Pin diffutils to 1.3.0
Add more collection construction helpers
Fix JavaElementDeltaFlag constant names
Add more resource helpers
Update some core persistence internals
Improve MatchingNode API
Add NodeDifferencer interface
Update Serializations internals
Refactor and generify CompilationUnitDifferencer
Draft CompilationUnitDifferenceListener
Bump feature and plugin versions