QSnake is a snake which eat color balls .Different color means different result.
All balls will raise the score, and the red one will reduce the tile of snake, and the yellow one will slow down
the speed of snake, and the green one will get more balls.
QSnake is a game with gesture.When fling to left, snake will move to left. When fling to right, snake will move to
right. When scroll up,snake will move up. When scroll down, snake will move down.