Add support for breaking long links

Before:

![screenshot 2014-09-10 15 18 19](https://cloud.githubusercontent.com/assets/1451471/4217938/066a29f0-38ed-11e4-8bb0-10657bda87f3.png)

After:
![screenshot 2014-09-10 15 18 28](https://cloud.githubusercontent.com/assets/1451471/4217939/066affec-38ed-11e4-988c-e828031dd11e.png)