Starting fedgate with and without services online

[rosshadden]

Fedgate needs to be fault tolerant and work even if its associated services are not online.

Right now fedgate expects associated services to be running by the time it starts up. I had envisioned more of a fluid workflow that accepts services into the fold as they come online. Should this not be possible we need to implement a hard stop upon startup, or a locking process that waits until all associated services are online.

Whatever we do should also handle services going offline as well, even if they were online when it started.