Add 'restart' command

[parrotmac]

What kind of change does this PR introduce?

Feature! Requested in https://github.com/supabase/cli/issues/234

What is the current behavior?

Doesn't exist

Please link any relevant issues here.

https://github.com/supabase/cli/issues/234

What is the new behavior?

Specifying the restart command will bring down services, then bring them back up.

Feel free to include screenshots if it includes visual changes.

Additional context

I also found myself restarting my stack a bit, so I added this feature and have found it useful.