[Observium] Reduce your storage IO with rrdcached

There was some discussion on IRC the other day about rrdcached and how it can be used with Observium to reduce your storage IO a lot when polling a huge amount of interfaces. However, not a lot of documentation exists yet on how to get rrdcached to work with observium. I did some trial and error and found a working method and wrote a quick and dirty guide. You can find it here: http://blog.best-practice.se/2014/10/using-rrdcached-with-observium.html Feedback is highly appreciated!

/Markus