Given GO ids and the obo_dag, create a plot of paths from GO ids.

def plot_gos(fout_img, goids, go2obj, **kws):
    """Given GO ids and the obo_dag, create a plot of paths from GO ids."""
    gosubdag = GoSubDag(goids, go2obj, rcntobj=True)
    godagplot = GoSubDagPlot(gosubdag, **kws)
    godagplot.plt_dag(fout_img)