This change introduces a replacment for planet.archlinux.org which uses
a python 2 project to generate static html from multiple RSS feed
sources. For archweb a set of 'static' feeds can be created in the
django admin view for the Arch forums and other static feeds, archweb
users can add their own blog rss feed in their profile which will create
a Feed model.
When running the update_planet command, all Feed models are iterated
over and the rss feed is parsed. The latest FeedItem is queried matching
the current Feed model and every newer entry in the RSS feed is added as
new FeedItem. Since the body is also stored in the FeedItem there is a
limit to the amount of FeedItems per Feed configured in settings.py of
which the default is 25.
When a user is marked as inactive his Feed model and items are
removed automatically to avoid keeping stale data around.
Closes: #261
