Correct the Balance Wii Board conection checker, isConnecting().
Some methods added to the class WiiBoard
Loc guessCoG() : the estimation of the center of gravity
boolean isleftZone() : is the CoG on the left side of the board
boolean isTopZone() : is the CoG on tne top side of the board
boolean isCentralZone(float tol) : is the CoG on the central zone, gibven torelance
boolean isCentralZone() : same as above, and the torelance is set to 0.4.