Flags in language list

I found this CSS library to easily insert flags: http://www.github.com/lipis/flag-icon-css.
So I thought it would beautify the language selector if the language links had preceding flags. Below is a screenshot how the page header looks like with the patch applied:

![flags](https://cloud.githubusercontent.com/assets/1278210/2754467/7e1c44b8-c955-11e3-929c-2872296f6dae.png)