Responsive redesign

The Thorax site wasn't responsive, but now it is! Some benefits aside from the shiny design that works on all kinds of screens:

- Home page delivered in 10 requests. (API Reference and Getting Started in 7).
- Home is 250kb before gzipping. (This will go down to 230 once this goes live and we can remove an extra font from Typekit, and should shrink considerably with gzip).
- Retina ready.
- Tested on all modern desktop browsers, IE8, iPad, iPhone, Android 2.2, Firefox Mobile, Opera Mini. (Opera Mini's 'monospace' font is horrible, so code samples are a little weird, but it works well other than that.)

Screenshots:

![screen shot 2013-08-05 at 9 42 06 am](https://f.cloud.github.com/assets/808159/911684/e36064fc-fdf0-11e2-96d0-4318bc59e3ba.png)
![screen shot 2013-08-05 at 9 42 35 am](https://f.cloud.github.com/assets/808159/911685/e59d1ec2-fdf0-11e2-889e-f975d40d5f06.png)
![screen shot 2013-08-05 at 9 43 33 am](https://f.cloud.github.com/assets/808159/911686/e7b939c0-fdf0-11e2-9904-0be62adab191.png)
![screen shot 2013-08-05 at 9 43 57 am](https://f.cloud.github.com/assets/808159/911687/e909eb6c-fdf0-11e2-9bf3-ade1c54d4f65.png)

// @eastridge