user wants to see bounce effect on icon on root_path

This feature adds a subtle bounce effect to the icons on the homepage to enhance the subtle experience. The code has been reviewed and tests have passed locally. No risk as this is a design change. 
![screenshot 2014-04-08 15 54 55](https://cloud.githubusercontent.com/assets/331004/2648470/d09a8aa4-bf57-11e3-88e0-58cbc0ca4721.png)