Labs page

This:

- Removes "jobs" from the navbar in favor of a "Labs"
- Adds an "ADI Labs" page
- Changes some colors around for consistency across pages.
- Changes the callout (yellow stripe) to be a "Learn to Program" prompt, as opposed to "Projects"

Relevant pages in their new form:

![blog](https://cloud.githubusercontent.com/assets/2433509/4227655/d57ae23c-3949-11e4-94b2-8e96ea6948fe.png)
![contact](https://cloud.githubusercontent.com/assets/2433509/4227656/d57b1766-3949-11e4-9d61-9984c1ae70b9.png)
![home](https://cloud.githubusercontent.com/assets/2433509/4227657/d57b7bde-3949-11e4-82f5-d020f424a6b3.png)
![labs](https://cloud.githubusercontent.com/assets/2433509/4227654/d5780738-3949-11e4-8217-1b2eea8f5b9a.png)