Upgrade to Launch Design

Upgrade to @bmartinstudio's awesome launch design, including:

* **Font**: Source Sans Pro
* **Menu**: Streamline navigation & add logo (placeholder)
* **Homepage**: Upgrade content & add calls to action
* **Buttons**: Use fancy [Foundation](http://foundation.zurb.com) buttons everywhere
* **Icons**: Install fancy [Foundation Icons](http://www.zurb.com/playground/foundation-icons) (#26)