Added Enterpries pages

Added a top nav for cloud and enterprise selection

 *  [ ] pypi mirror docs
 *  [ ] installer docs
 *  [ ] command line configuration

![screenshot 2014-08-06 07 25 47](https://cloud.githubusercontent.com/assets/741611/3828294/7c22fd26-1d76-11e4-9089-36e380b0bb0f.png)