Sombrero(s)

Adds two sombreros to the code, one is vend-able at the autodrobe, and t...he other is admin-spawnable, since, like golem clothing, you're unable to take it off yourself.
A generic version might be coming, since I'm just lacking an icon_state that I might get soon.

Thanks to MattyQ for the sprites
![greensombrero](https://f.cloud.github.com/assets/5836184/2250639/766647e4-9d92-11e3-8587-22ff37239521.png)
![shamebrero](https://f.cloud.github.com/assets/5836184/2250640/7a51b1d6-9d92-11e3-9760-11f752503d24.png)
![greensombrero1](https://f.cloud.github.com/assets/5836184/2250643/7cf3b70e-9d92-11e3-9ffb-678cdc191c74.png)
![shamebrero1](https://f.cloud.github.com/assets/5836184/2250644/802c7118-9d92-11e3-9322-4fe514644f61.png)
![shamebrero-onperson](https://f.cloud.github.com/assets/5836184/2250646/83a6a606-9d92-11e3-9d3d-ed73135b13e4.png)