/* $DOC$
   $NAME$
      ft_SysMem()
   $CATEGORY$
      DOS/BIOS
   $ONELINER$
      Determine the amount of conventional memory installed
   $SYNTAX$
      ft_SysMem() -> nMemSize
   $ARGUMENTS$
      None
   $RETURNS$
      A numeric corresponding to the number of KiB memory.
   $DESCRIPTION$
      ft_SysMem() simply reports the amount of conventional memory
      installed.
   $EXAMPLES$
      ? "Conventional memory:", hb_ntos( ft_SysMem() ), "KiB installed"
   $END$
 */