Adds the Clown Borg and two emag only items for it.

All sprites except for the peel generator by Mechoid.
![clown](https://cloud.githubusercontent.com/assets/4081722/2825497/29553192-cf4f-11e3-90e3-b07162ed8e3f.jpg)
![happy_clown_by_michellica](https://cloud.githubusercontent.com/assets/4081722/2825494/29547cca-cf4f-11e3-8a50-01388ed7cf95.jpg)
![hello-clown-small](https://cloud.githubusercontent.com/assets/4081722/2825495/29549304-cf4f-11e3-90ef-803e6f12c498.jpg)
![quiz-header](https://cloud.githubusercontent.com/assets/4081722/2825499/29562afc-cf4f-11e3-8f8b-4d9893117ada.jpg)
![stock-photo-happy-clown-pointing-to-the-copy-space-area-129810059](https://cloud.githubusercontent.com/assets/4081722/2825496/2954c37e-cf4f-11e3-8f87-da3d15c4f116.jpg)
![wernie-the-clown](https://cloud.githubusercontent.com/assets/4081722/2825498/2955505a-cf4f-11e3-9520-96d24302cfe0.jpg)