Add resource class to cookbook version show

:fork_and_knife: The resource class contains a bunch of useful styles for resource show views without things just don't look quite right.

From

![screen shot 2014-07-23 at 7 32 03 am](https://cloud.githubusercontent.com/assets/316507/3672307/4fdfc6fa-125d-11e4-9dec-98b3c1ddbb2d.png)

To

![screen shot 2014-07-23 at 7 32 17 am](https://cloud.githubusercontent.com/assets/316507/3672309/534901bc-125d-11e4-8804-66a2084fc696.png)