Wrj4P5

Correct the Balance Wii Board conection checker's bug, isConnecting()

and

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.