making sure images don't go more than width of container

Fix for images breaking out of container.

Before;
![screen shot 2014-05-06 at 09 55 17](https://cloud.githubusercontent.com/assets/1303616/2887525/68a36014-d4fc-11e3-8c59-735c50fd6df0.png)

After;
![screen shot 2014-05-06 at 09 57 25](https://cloud.githubusercontent.com/assets/1303616/2887532/7b3d5e0a-d4fc-11e3-9fae-802b5ed64d23.png)