twScroll( Lines, wBorder, wT, wL, wB, wR, wColor )
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     Scrolls all or part of a window a specified number of screen
     lines.


       Arguments:

     Lines   - 'N' Number of lines to scroll. Negative numbers indicate
                   UP, positive DOWN. The function only performs when
                   this parameter is positive.

     Border  - 'L' Include or Exclude the border, whether in a box or a
                   window. Defaults to .F. When referring to a screen
                   region other than the whole window, this parameter
                   sees the border as that on a box within the window.

     wT,wL
     wB,wR   - 'N' Relative Window Coordinates. This defaults to
                   display area for the current window if not passed.

       Return:

     Current window handle.

       Example:

     twScroll( -1, .T., 10, 5, 18, 26 )

     Scrolls the box at relative screen coordinates 10,5,18,26 up one
     line, including the border area.

     twScroll( 10, .F., 10, 34, 18, 55 )

     Scrolls the box at relative screen coordinates 10,5,18,26 down ten
     lines, excluding the border area.

     twScroll( 5, .F. )

     Scrolls the current window, excluding the border, down 5 screen
     lines.