Legend()

         Draws and fills a square and a text optionally

    Syntax:

         Legend ( nX, nY, nSize, nColor, cText ) -> Nil

         nX      : Left upper coordinate X of the square
         nY      : Left upper coordinate Y of the square
         nSize   : Size of the square
         nColor  : Colour of the square
         cText   : A text asociated with this colour in the legend

    Description:

         This function already existed on version 1.25 of Fast, though
         it was not documented due to it was used internally by GraphBar().
         Now, with the inclusion of GraphTart() it is allowed for the user
         to create the legends where and when he likes and that's why it
         has been documented.

    Return:

         Nothing.

    Example:

         SetVGA()
         cTitulo := "Fast Graphic System"
         GraphTart ( 320, 240, 100, { 17, 3, 15, 60, 15 } )
         DispStr ( cTitulo, 320 - Len ( cTitulo ) * 4, 370, 15, 0 )
         Legend ( 320, 460, 15, 4, "Fast Library" )
         Inkey (0)
         TxtMode ()