Don't call expire when processing remote invalidation of clustered session

When JBC notifies JBossCacheManager that the root node for a session has been invalidated via a remote call, JBMC.processRemoteInvalidation() calls Session.expire on the local session (if there is one). The expire call includes flags that result in no notifications being sent to any listeners.

I don't see any point to this expire call if there are no notifications. The other work expire does is removing content from JBC, but the remote invalidation that triggers all this is already removing that content. Just drop the session from the local session map. Perhaps flag the session so if there is a concurrency/sticky-session problem and a local request thread is handling the session it knows the session is invalid.