Upped cache times.

I want to see if significantly larger cache times have on effect on hit ratio and 'freshness of content'

At the moment we tend to do between 55% & 65% hit ratio. I am going to see if this goes up. It got up to about 70% in a lesser test (changing 1 minute to 2 minutes).

![hitratio](https://f.cloud.github.com/assets/76709/854681/d322e1b6-f50b-11e2-8f69-d0f0b064cfa0.png)