Removed persistence tests.
Removed persistence, and minor refactor.

Removed duplicate event handling code, and added test for getting
entity ids from a gen_event manager.
Merge pull request #23 from SkewedAspect/bug-mw-removed-entity-event-persistence

Bug mw removed entity event persistence
Merge remote-tracking branch 'origin/master' into feature-ccase-com-layer-cleanup