BUG: Add a test that checks file paths after MRML and MRB save/load

Add a test that checks the paths in the scene with saving to mrml (have to force
a write of a sample data node since the saveScene call only writes out the MRML file,
no storage nodes are triggered to write) and MRB and reloading and saving to MRB.
Remove skipping the master scene view as paths of storage nodes there do need to be updated.
TBD: fix the paths after saving the MRB a second time (they get reset to the deleted bundle directory from the first MRB save).

Issue 0003956

git-svn-id: http://svn.slicer.org/Slicer4/trunk@24394 3bd1e089-480b-0410-8dfb-8563597acbee