Hoop station upgrade

Hoop station upgrade from @ImTheFish, taken from [this forum post](http://spacesimcentral.com/ssc/topic/3377-modeling-task-hoop-spacestation/?p=36537):

![](https://f.cloud.github.com/assets/130670/141797/2885e354-7273-11e2-9f53-1ec148ca0323.png)

Still to do:

* Hook the door animation up to the game
* Redo the interior animations points to make use of the space (more bays)
* Get assets onto the assets repo (though I'll wait until this is merged to allow for further updates)

Please pick these jobs up if you feel so inclined. In particular I haven't done animation points before, so you might be able to do them faster than me :)