[From @joshdata: This is part of @toilal's work in #377 and 1eb77c332b. The changes are:
* Separates out the runit configuration from starting Mail-in-a-Box setup so that Mail-in-a-Box setup does not block the starting of runit services and we can assume that runit is running during setup (i.e. we can restart services).
* Adds a SKIP_INSTALL flag so that the container can be restarted without re-running the whole Mail-in-a-Box setup.
* Made containers/docker/run more flexible.
* I'm also adding some "|| exit 0"s to the run script to stop if there are any docker errors.
* I'm also adding the prereqs installs from questions.sh into Dockerfile so we don't have to reinstall each time.
]
Docker support was initially worked on in 2bbb7a5e7e, but it never really worked.
This extends f7d7434012800c3572049af82a501743d4aed583 which was an old branch for docker work.
Toilal
Joshua Tauberer
Morteza Milani
Paul Jimenez