Users can delete their own listings

https://trello.com/c/Vn7cGtQO/42-delete-listings

![image](https://cloud.githubusercontent.com/assets/8669803/5095126/d484ad1a-6f34-11e4-90e1-f140dc85b03c.png)

![image](https://cloud.githubusercontent.com/assets/8669803/5095128/dc3f3a98-6f34-11e4-8830-072dbf2a3804.png)
Gotta be honest, I'm liking the whole "marketplace" thing less and less. Really feels like that should just be the listings#index (and be called "marketplace", you can even make a route alias if you want the URL)