We want to migrate to mailman3 as mailman2 is basically unmaintained and
requires Python 2 which is EOL.

Because the mailman and mailman3 packages conflict and we don't want to
perform a big bang migration, mailman3 must be deployed on a separate
server. mailman-web (mailman3's web interface) hasn't been packaged yet,
so for now we are using my homebrewed PKGBUILD[1].

[1] https://gist.github.com/klausenbusk/5982063f95c503754a51ed2fefb8915e

Ref #59

It has been killed by systemd-oomd a few times recently and we don't
want to start it manually every time it happens.

The DNS is still pointing to luna.

The redirects are now done by the `redirects` role.

yaml: truthy value should be one of [false, true] (truthy)
yaml: wrong indentation: expected 4 but found 2 (indentation)
yaml: too few spaces before comment (comments)
yaml: missing starting space in comment (comments)
yaml: too many blank lines (1 > 0) (empty-lines)
yaml: too many spaces after colon (colons)
yaml: comment not indented like content (comments-indentation)
yaml: no new line character at the end of file (new-line-at-end-of-file)
load-failure: Failed to load or parse file
parser-error: couldn't resolve module/action 'hosts'. This often indicates a misspelling, missing collection, or incorrect module path.

To correctly be safe for CVE-2016-1247, we need all nginx log dirs
to be owned by both user and group root. Also, since nginx childs
runs as http user, the directories permissions must be 0755, so the
http user can descent into it. Since the logrotate will create the
log files as http:log, the nginx childs will be able to write to the
logs, but will not be able to create files inside those dirs, fully
preventing CVE-2016-1247.

Signed-off-by: Florian Pritz <bluewind@xinu.at>