OZP-807: Useful Backend Legacy service for translating OWF8 objects for OWF7 javascript.

1. Added javadoc comments.
2. Changed TranslationService to return ServiceModels when translating from OWF8 maps to OWF7.
3. Modified translation methods to take in parameters for domain objects passed in instead of expecting them on the map.
4. Added tests for translating OWF 8 widget definitions and personal widget definitions.