Provide ability to block/notify on RPC readiness on node startup

Currently, when a node joins the cluster, the members will receive a ViewChanged event. However, this does not mean you can act on it in all ways. For example, you cannot send an RPC command to the new member. If you do then he will respond with CacheNotFoundResponse because his ComponentRegistry is not set up with the cache yet. It would be helpful if there were some way to know when someone joined and they are fully functional.