API changes and internal changes.

Moves action from querystring to "/api/$action".
Renames response to creategame action from room_code to gameid.

Creates color and variant atoms on server start.
 (This is kinda terrible, but allows us to do binary_to_existing_atom
 later when we go to read the params in the setcolor action.)
Changes player, game, and querystring handling to map rather than record.