Set xcuserdata files to be ignored.
Removed release messages to unsafe_unretained properties. (Assigned some to nil to avoid dangling pointers instead)
Removed synthesise and custom getter and setter for player property in PlayerStore.
    Set the player object in Player Controller to unsafe_unretained to better reflect the proper parent-child relationship. (Previously, the custom getter/setter + synthesize was causing the Player Store to not have a strong ownership of the player object)