Standardize JS properties/YUI Attributes

[schancel]

There is currently some duplication of using YUI Attributes and JS properties for the same information at the same time. This should be standardized across the modules.

Suggest adding a YUI attribute to the player. The other modules can subscribe to change events, and update their local JS property accordingly. This will allow the board and renderer to adjust themselves if a multi-game SGF file changes the board size between games.