Doodle or Die, Node Knockout winner for Most Fun, updated

[request] Added brown, gray, and orange.

[request] Added undo, faster clear.

[request] If you paint outside the edge you can keep painting.

[new] Cursor changes to match paint color.

[fix] Images are now served as client-cacheable files instead of base64 encoded strings in the html loaded from MongoDB. (HUGE speed impact.)