BoxTurn()

         Turns on/off a window with light focus

    Syntax:

         BoxTurn ( aBox [, lMode] ) -> Nil

         aBox  : An Array value with a light focus window
         lMode : The new visual mode. ( By default: .T. )

    Description:

         Reverses the orientation of a focused light window. If lMode is
         true, the window shows up in the normal way. Otherwise, the
         window shows up as pushed.

    Return:

         Nothing.

    Example:

         BoxTurn ( aBox, .T. )