Previously copying elements within or between diagram editors and also
copying diagrams in the model browser would preserve GUID identifiers
for the diagram ordered set structure itself and all its elements. The
correct behavior is now implemented which is to force the system to
generate new GUID identifiers for all copied structures that have
identifiers.
refs #7348
Change-Id: I811bb4a118ffb9321577ef46f6651459379cdd08