Move description to top of page

This PR moves package descriptions to the top of the page, below the package title/latest version, but above it's corresponding line break. It also changes the description to a `span` instead of a `pre` block, making it fit into the page a bit more.

The main reasoning behind this is to be able to to read the description without having to scroll to the bottom of the page.

:mushroom: :lemon: 

__tl;dr__

![screen shot 2014-10-04 at 1 22 22 pm](https://cloud.githubusercontent.com/assets/860934/4514545/a69394d0-4b75-11e4-828b-376c28129e27.png)