Make UI elements larger

[dustinsgoodman]

The game play area and controller are only taking up about 1/3 of the screen. This makes the video element too small for debug purposes and doesn't use enough real estate. Let's do the following:

• Make the game grid 20x15 (currently 15x10)
• Make the tv and controller take up 60-80% of the screen instead of 30-40%
• Make the video on the controller larger by at least 2x
• Make the snake's eyes 2-3px wide instead of just 1px