New tile, new features! (0.8.0)

New features:

• Set the maximum time while you would like to play the game
• Random coundown tiles which has higher value but gives negatives points in case you can't catch them in time
• Moving tilesets in the menu to make the game nicer :)

Fixes:

• Tiles are not in front of the pause or game over menu anymore
• In web mode the "Quit" function is disabled