Blog redesign

A work in progress to split out the blog from the documentation layout into its own thing. Focus on content rather than trying to cram it into a layout that needs to be improved too (the doco layout).

Currently looks like this:

![](http://s3itch.paperplanes.de/Travis_CI_Blog_The_Travis_CI_Blog_20130716_151244.jpg)

Included changes so far:

- Paginate over three full blog posts rather than the first 75 words of seven blog posts
- Slightly wider layout
- Removed sidebar for navigating the documentation