MSE_Exit() -> nil

  Deinstalls the MouseDriver and restores the Videostatus

                      ATTENTION!!                

  ##
  #  You've got to call MSE_Exit() before you leave your application,
  #  otherwise your Computer will give up <g> when the mouse is moved



  This also happens, when your programm is terminated in an abnormal way
  (any Bugs ?)  Best thing to do is include this function in Errorsys.prg
  or declare MSE_Exit() as your Exit Procedure. But maybe you just love
  to boot ?