[WFLY-490] / [WFLY-1618] Add RollbackHandler(s) to the role mapping add/remove operations.

Also update the operations to fail if inconsistent runtime state is detected.  It should not be possible for the runtime state to be out of synch as the model is always updated first - however if it was detected that it is out of synch the only option is to restart the server.

Also minor test update, we never added the role so should not be removing it.