Add description for Google

This adds a couple descriptions for Google, to avoid our current situation:

![screen shot 2014-08-04 at 9 57 24 pm](https://cloud.githubusercontent.com/assets/1435836/3814425/1841ef76-1cbb-11e4-91e9-6d6f8bd5a9d3.png)

(It also fixes the capitalization of Mapzen and Mapbox.)