Fixing image gallery on content.html

![screen shot 2013-06-06 at 3 00 58 pm](https://f.cloud.github.com/assets/807586/617999/32e9ea88-cea9-11e2-9f58-4460775b14b8.png)

This looks a bit strange as you can see in the screenshot (because the images had a different aspect ratio). Also, I fixed a typo in README.md