The synapse demo was a bit flakey in terms of supporting federation. It turns out that if your computer resolved `localhost` to `::1` instead of `127.0.0.1`, the built-in federation blacklist specified in `start.sh` would still block it, since it contained an entry for `::/127`. Removing this no longer prevents Synapse from contacting `::1`, federation works again on these boxes.

* Remove deprecated 'verbose' cli arg

* Create 5725.bugfix

This reverts commit dc7cf812.

Configure the demo servers to use untrusted
tls certs so that they communicate with each other.

This configuration makes them very unsafe so I've added warnings about
it in the readme.

start.sh: Fix the --no-rate-limit option for messages and make it bypass rate limit on registration and login too.

Manually generate the default config yaml, remove most of the commandline arguments for synapse anticipating that people will use the yaml instead. Simpify implementing config options by not requiring the classes to hit the super class