Core needs to track and report on reachability of adapters from core

After an adapter container registers with the core the, the core seems to remember it even if the adapter container is stopped and removed.

The core should recognize when an adapter container "goes away" and automatically unregister that adapter. We might want to time delay it (i.e. the adapter goes from a "ready" state, to an "LOS" state, and then finally is unregistered to help smooth over adapter container restarts).