Game: Correct handling of null tiles.

git-tfs-id: [https://tfs.codeplex.com:443/tfs/TFS15]$/Atomix;C40963
Game: Indicate if hand is tracked by KinectCursor.

git-tfs-id: [https://tfs.codeplex.com:443/tfs/TFS15]$/Atomix;C40964