Docs styles update

Closes https://github.com/dotcloud/docker/issues/6514
Closes https://github.com/dotcloud/docker/issues/6377
Closes https://github.com/dotcloud/docker/issues/6514
Closes https://github.com/dotcloud/docker/pull/6502

Eg:

![screen shot 2014-06-18 at 16 11 03](https://cloud.githubusercontent.com/assets/6561122/3321839/d7cc9bdc-f73d-11e3-9e85-a13648fafc5d.png)