Ou selector: active unit is now included in the unit's list.

We decided that the select orgunit should also be displayed in the selection list.
![bildschirmfoto 2014-06-24 um 07 46 26](https://cloud.githubusercontent.com/assets/485755/3367560/f0e7fb4c-fb62-11e3-8120-63786616c325.png)

Some special styling for the active orgunit is arranged. 

@deiferni please take a look.