Admin menu - user info

In the administration the menu in the left column contains the user image or fa icon and user's name and surname. It should contain a user group name as well where the currently logged in user belongs to.

However instead of this a link (non-clickable) to the user groups management was displayed. I have fixed this - retrieving the user group name only if $user_info is available.

I have fixed HTML/CSS formatting a little so that the displayed information now looks better.
![user-info](https://cloud.githubusercontent.com/assets/1033137/3896870/5df93532-225c-11e4-9d6d-65864a8abb56.png)