Bug Fixes! Game version to 1.3.4

Things improved:

• Game has low framerate when playing the background music: Changed mp3 to wav so the console decodes faster the song
• Refactor of the code, now it is more legible: And it will be even more in the future.
• Changed difficulty: Now snake moves once per 4 frames, each 4 points gotten, snake will move 1 frame faster until it moves once per frame (making it go faster).
• Music and inverted colors status saved between games.