Add RTL display option on metadata component

Add an option to the metadata component to display in RTL for languages
which use RTL text such as Arabic.

This would look like this in the guide:

![screen shot 2014-12-01 at 13 52 52](https://cloud.githubusercontent.com/assets/35035/5246485/742f0e88-7961-11e4-984e-6824f446e145.png)