Create social network styling

* Import font awesome
* Add social network fa icons
* Create a grid and style social networks
* Add input box label
* Change handle `input` from id to class
* Add placeholder text to handle input box
* Change `white` to `$white` in hero section
* WIP: style `fa-at` and fix `body-content-container` padding

![screenshot 2014-11-26 01 14 32](https://cloud.githubusercontent.com/assets/5547897/5198735/d8105e90-7509-11e4-9262-15f369473b99.png)



very nice!