Fixed an Entity bug for Entities with non-placeholder URIs, cleaned up the client code, added a prov:pingback property to Entities, and added a TestClient class that is based on the Main test client class but more flexible.
Completed ServiceEntity, added placeholder.org to Activity, removed Dates from ExternalReport, added nativeId & reportingSystem to ExternalReport but should do so to Report and inherit.Updated Main to run
* Make Activity & Entity restorable from Model.* Add tests for restoring from Models.
* Add chained constructor to Entity.
* Add equality overrides to Activity & Entity.
* Add ability to reverse-lookup ConfidentialityStatus.
* Few minor method renames to match Java conventions.
Make test run on any* computer by creating temporary files as per system defaults rather than using specific files somewhere on Nick's computer ;).Remove a stray hash/pound that was causing a syntax error when serialising ExternalReports.