Issue #691: Store the current version of the HPO ontology in each patient record.
Created new event listener and a new XWiki class.
Issue #691: Store the current version of the HPO ontology in each patient record.
Renamed XWiki class to OntologyVersionClass. Other general cleanup.
Merge pull request #695 from soLEED/issue-691

Issue #691: Store the current version of the HPO ontology in each patient record.