RDF'ed serialization


- added new RDF format with IS_IN_FORMAT relation
- added separate RDFS_LABEL to the RDF format
- pointed object HAS_SERIALIZATION to RDF format
- added getSerializationTitle to bridge HAS_SERIALIZATION -> IS_IN_FORMAT -> RDFS_LABEL gap
- modified unit test
- updated views page

Resolves https://www.pivotaltracker.com/story/show/65221404