Retro Mode

This adds a Retro Mode to Kart.

Retro Mode essentially styles the UI to appear like it's on an older piece of hardware. It drops the animations and uses a pixel font. All things that an older machine probably would never have or support.

You can simply set this mode via the Settings.

![retromode](https://cloud.githubusercontent.com/assets/260/3886682/9c8aef78-21e1-11e4-9ebf-1786e7e2b7bd.gif)