Update to the 2019 conference report

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

Add some new systemd hardening features to network related services.

ansible 2.9.0 has a new git module feature gpg_whitelist which is an
array of allowed keys. If a tag or commit was signed with a different
key ansible aborts.

Signed-off-by: Jelle van der Waa <jelle@archlinux.org>

Signed-off-by: Sven-Hendrik Haase <svenstaro@gmail.com>

This enables lastlog so that we also see which accounts are used for
email only even if they are not used for SSH.

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

The wiki requires an nginx cache for mediawiki's static assets which are
served through PHP causing an exhaustion of php-fpm workers. Caching in
nginx is a good way to circumvent this.

Add a new subdomain for the static content (videos,photos) of our Arch
Linux Conference so it is independent of the the conf.archlinux.org url
routing.

The location block should also execute PHP otherwise we will just reply
with PHP files.

someone has made a conky script that hits the rss feed every second, so nginx
now limits that to once per minute, returning 503 instead at other times. a
burst is also in place to prevent genuine users being blocked.

luna handles mailman and other services that generate a lot of mail, so bypass
all rate-limiting for it.

Added arch-tu to mailman_compat.

mex.mirror.pkgbuild.com suffers from a disk failure so it can't act as a
proper mirror at the moment.