SNAKE improvement

This PR contains a fix according to @KA101's comment in #6253: dead body of snake gives you a clue that screen is for mini-game, not for a main game.
![game_over](https://f.cloud.github.com/assets/5421954/2239977/b25d2498-9c6b-11e3-9017-d04a7f0cc85e.png)


P.S. That's silly, I know. I. just. can't. resist.