eat from ground

upd: main post is out of date. Current state in the comments.

Portion of Items from smashed vending machine:

![1](https://cloud.githubusercontent.com/assets/6351438/3555098/82775fae-0913-11e4-9cc2-70753551b5a6.png)

Press `[E]`, press `Esc`:
All items from vending machine (doubles excluded):
![2](https://cloud.githubusercontent.com/assets/6351438/3555105/9f8b7288-0913-11e4-9133-eae04549e52f.png)


Again, please take a look at inventory::form_from_map().  Also take a look at item::is_food().  You're doing a lot of stuff here that is already handled elsewhere.