ENH: Added test for MRML node reference serialization and parsing
Issue #3416

From: Csaba Pinter <csaba.pinter@queensu.ca>

git-svn-id: http://svn.slicer.org/Slicer4/branches/Slicer-4-3-1@22701 3bd1e089-480b-0410-8dfb-8563597acbee
ENH: Slicer 4.3.1-1

git-svn-id: http://svn.slicer.org/Slicer4/branches/Slicer-4-3-1@22704 3bd1e089-480b-0410-8dfb-8563597acbee