Style User Account pages

This PR aims to fix two issues:

1). Hovering over a user role used to display an error message with "you may not create user::roles".
2). Improving the visibility of active user roles.

Very open to feedback as this may not be the best fit for the style of the site.

![screen shot 2013-07-27 at 12 50 32](https://f.cloud.github.com/assets/950333/866814/be9ec128-f6b5-11e2-88f1-5ab66a2ad705.png)