Install, configure, and run Gitea.

**Role Variables**

.. zuul:rolevar:: gitea_reverse_proxy
   :default: False

   Create an Apache reverse proxy listening on port 3081.  This can be
   useful for OSI layer 7 filtering; e.g. matching bad User-Agent
   fields.

.. zuul:rolevar:: gitea_reverse_proxy_hostname
   :default: inventory_hostname

   The name of the hostname to reverse proxy to.  Only necessary for
   testing where we do not have a certificate for the hostname.