XPmouseSens()
 Get/Set the Mouse Sensitivity
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   Function:   XPmouseSens()

               Returns and optionally set's the Mouse Sensitivity.
               The sensitivity defines the speed of movement, according
               to the movement one does with the mouse.

   Syntax:     XPmouseSens([nNewSens]) --> nSens

  Arguments:  nNewSens is an eventual sensitivity to set.
               0 means none at all (mouse cursor won't move),
               100 is very fast. Good Average is 50-60..

  Returns:    The currenct sensitivity, prior to setting the
               new sensitivity.

  Usage:      XPmouseSens(70)  //My default..