Plot GO DAGs for all groups of user GOs.

def plot_groups_all(self, fout_dir=".", **kws_pltargs): # GrouperUserGos
        """Plot GO DAGs for all groups of user GOs."""
        hdrgos = self.grprobj.get_hdrgos()
        pltargs = PltGroupedGosArgs(self.grprobj, fout_dir=fout_dir, **kws_pltargs)
        return self._plot_groups_hdrgos(hdrgos, pltargs)