[games] Players should be able to see the rules of the current game

[wamanuz]

The rules and instructions should be visible to the players. This can be done by adding a variable to each game, and output it in the template. Make sure that the rules are formatted in a stylish way and that the text can have variables in the, e.g. the k in mnk-game.

[Zetro]

Duplicate of #24?

[wamanuz]

Yup