Add Hound logo to home page

* Add Hound SVGs to home page
* Move line on homepage to the left

https://trello.com/c/U2GJGKlo

![screen shot 2014-06-13 at 3 20 11 pm](https://cloud.githubusercontent.com/assets/816402/3276457/a05e4cbe-f34a-11e3-8b34-b9ae26b55545.png)
![screen shot 2014-06-13 at 3 20 02 pm](https://cloud.githubusercontent.com/assets/816402/3276458/a05f2184-f34a-11e3-886d-193548f987a9.png)

We could change the logo's color and the other purple to the old purple. I can do this in the next commit.