Adds number of comments to title.

def get_title(self, group=None):
        """Adds number of comments to title."""
        title = super(CommentsPlugin, self).get_title()
        if group is not None:
            count = GroupComments.objects.filter(group=group).count()
        else:
            count = None
        if count:
            title = u'%s (%d)' % (title, count)
        return title