[PR] Adjust formatting and flow of the custom CSS language

Suggested changes (by me) to the custom CSS intro text. Screenshot shows how this looks in the admin:

![screen shot 2014-09-18 at 4 14 41 pm](https://cloud.githubusercontent.com/assets/286171/4328683/ad2b7aa8-3f89-11e4-9046-41f73c59064a.png)

@natejacobson - any thoughts? I wanted to get some whitespace in there. :)