* Ensure a useful logfile gets recorded for synapse startup failures
* Update synapse config to stop complaining about key servers
* Add flag to turn on registrations again
From https://github.com/matrix-org/synapse/pull/12091
* Use the shared secret registration API directly
rather than invoking the synapse module to do it. It's probably
a bit simpler, if anything, and allows for synapse to be run in
a separate container (or rather, avoids the javascript having to have
a copy of synapse source & server config).
* Make registration secret required
Update commander (8 major versions!) to get requiredOption
* Wrong options object :/
