Reworked documentation for GitHub pages website.

- Use couscous (https://github.com/mnapoli/Couscous) to mirror repository documentation on the website.
- Added a bit of design based on Bootstrap and the Bootswatch Superhero theme (http://bootswatch.com/superhero/).
- Updated documentation with content from current GitHub pages site.

Updating documentation should now be a matter of installing couscous and running “couscous deploy”.

The result should look something like this:

![deployotron-website](https://cloud.githubusercontent.com/assets/1658559/4517760/b627011e-4c53-11e4-9a8b-c0366fd1665c.png)