Add possibility to wrap over a field for Snake.

Change-Id: Ibe5e73154354ead533ce6778b3fef355d47664b8
Add possibility to play game with 2 Snakes.

Change-Id: Iac33982ae95cb96cb0d04f5437de82650a96d712
Can load game from config file.

Change-Id: Iab7a07e24114c9a01ef6230e455ec9083b3c7a15