Some users report munin is broken because munin and munin-node disagree about the name of the machine. I think this occurs if hostname (used by munin-node) reports a different name than PRIMARY_HOSTNAME (which we put in the munin config).
Hard-code PRIMARY_HOSTNAME in munin-node.conf.
Fixes#474.
See https://discourse.mailinabox.email/t/404-not-found-on-admin-munin/623/24.
* install the munin-node package
* don't install munin-plugins-extra (if the user wants it they can add it)
* expose the munin www directory via the management daemon so that it can handle authorization, rather than manintaining a separate password file