ServiceUser ownership status instead of removing

- add new method ableOwnership to impl which set status=0 for ownership
- add new method disableOwnership to impl which set status=1 for ownership
- add new method serviceUserOwnershipExists which get true if some relation in DB exists, false if not
- add status condition (status=0 | 1) to all get methods (working with ServiceUsers and Users)
- modify method addServiceUserOwner to choose if want to add new ownership or modify existing
- modify method removeServiceUserOwner in BlImpl to only disable ownership (set status=1)
- add a lots of tests for serviceUser actions
- modify method deleteUser in BlImpl to allow removing ownership even if deleted user is the last owner of serviceUser
- modify AuthzResolverImpl query to get only enable ownerships
- fix method getServiceUsers (for PostgreSQL)
Merge pull request #118 from stavamichal/ServiceUserOwnership-behavior

ServiceUser ownership status instead of removing