* Refactor weighted-settings.js
This moves most of the infrastructure into two classes:
* WeightedSettings covers the settings page as a whole. It tracks the
user's current settings in local storage as well as the game data
from the server so they don't need to be manually passed around from
function to function.
* GameSettings covers the settings for a single game, and provides a
view of the current settings and the game data just for that game.
* Fix item count updating