[keycloak-dev] Status on model splitting

I've implemented JPA realms, users and sessions, as well as mem sessions. It also works fine with the cache. I still have a bit of work to do before I can commit it though. I'd like to do some clean-up as well as implement Mongo providers. In the mean time if anyone needs to do any minor changes to the model just go ahead, and I'll merge it once I'm ready (hopefully early next week).