Support multiple deployments

[code-asher]

If you have connections in your recents from different deployments only the ones from the most recently configured deployment will work.

Some ideas:

1. Always run config-ssh before connecting so that deployment gets put into the config.
2. Use separate SSH configs per deployment URL so they will not clobber each other.
3. Provide the config values and avoid external config files entirely.
4. Modify the Coder CLI to support multiple deployments (maybe some kind of prefix).
5. Same as 4 but implement in the plugin (so re-implement config-ssh basically).