oWin:circle( <nRow>, <nCol>, <nRadius> ) -> NIL

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 PARAMETER:

  <nRow>,<nCol> represent the center of the circle to draw. This coordinates
                are relative to the Window, and measured in pixels

  <nRadius>     Is the (pixel)radius of the circle


 DESCRIPTION:

  This method draws a circle on the client area of the window. All the
  windows API stuff like getting and releasing a Device Context, 
  invalidating the area and calculating the circle is automatically
  handled by FiveWin.