Use munin config to send emails and produce graphs using cgi.

After updating monitor to using Raring, it turns out that the version of
munin has been bumped to v2.0. This has the \"{u}ber exciting feature
that it can use cgi to generate graphs. Therefore we can do all sorts of
zooming in to understand what's going on!
Updated munin config to support munin v2.

This gives us cool features, such as a hot new template, and cgi graphs
that let us zoom in!