Corrected some little details.

 On branch master
 Changes to be committed:
	modified:   __pycache__/directions.cpython-33.pyc
	modified:   __pycache__/food.cpython-33.pyc
	modified:   __pycache__/game.cpython-33.pyc
	modified:   __pycache__/snake.cpython-33.pyc
	modified:   __pycache__/tile.cpython-33.pyc
	modified:   directions.py
	modified:   food.py
	modified:   game.py
	modified:   main.py
	modified:   snake.py
	modified:   tile.py