[WIP][CR]  Boats 

Add to game boats.

A while only inflatable boat:

![excursion_3_inflatable_boat](https://cloud.githubusercontent.com/assets/6351438/3489118/f5901d24-0516-11e4-8aa2-95d226f22c8f.jpg)

You can fold/unfold it to carry in inventory and unpack near water. 

Engine - Paddles. It like pedals, but paddles.

Boats can swim by deep and shallow water. On the ground you can grab and drag the boot (or fold it to inventory).

You can fish from boat! Romantics!

![fish](https://cloud.githubusercontent.com/assets/6351438/3489136/2242b36c-0518-11e4-8970-1dcd376280f4.png)