Plot a single page.

def plt_goea_results(fout_img, goea_results, **kws):
    """Plot a single page."""
    go_sources = [rec.GO for rec in goea_results]
    go2obj = {rec.GO:rec.goterm for rec in goea_results}
    gosubdag = GoSubDag(go_sources, go2obj, rcntobj=True)
    godagplot = GoSubDagPlot(gosubdag, goea_results=goea_results, **kws)
    godagplot.plt_dag(fout_img)