Message()

         Displays a string to the screen

    Syntax:

         Message( nY, nX, cMess [, cColor] ) -> Nil

         nY     : Y coordinate
         nX     : X coordinate
         cMess  : Message to write
         cColor : Optional color of query

    Description:

         Writes cMess in the given coordinates using cColor or the active
         colour if cColor is Nil.

    Return:

         Nothing.

    Example:

         Message ( 12, 15, "Hello", "R/B" )