It's small and ugly. Maybe show more columns (host, ...) and make it a bit more attractive.

It reports the full list of interfaces it listens on - this can be useful, but we should add an option to report only the host:port that is relevant for the mDNS interface we publish on.

At the moment, xpra supports this on the server: the xpra server stays alive even when shifter_server is stopped.
Ideally, we want to keep all the sessions running and just re-load the session files when the server re-starts. The problem comes from the fact that NX writes to stdout and we watch this output to get the current session state, we will need to redirect to a file instead and watch that (and maybe also start it with 'nohup'?)