BUG-2304 Fix SchemaContextUtil for augmented nodes.

Also keep backwards compatibility for invalid leafrefs
+ Fix the serialization in XMLStreamNormalizedNodeStreamWriter (btw. interesting name for a class)

Change-Id: I46cfcef46c97267c7e9b5bfebe03e42e9071e1e7
Signed-off-by: Maros Marsalek <mmarsale@cisco.com>
Signed-off-by: Jozef Gloncak <jgloncak@cisco.com>
Merge "BUG-2304 Fix SchemaContextUtil for augmented nodes."