Print GOATOOLS version and the date the GOEA was run.

def print_date(min_ratio=None, pval=0.05):
        """Print GOATOOLS version and the date the GOEA was run."""
        import goatools

        # Header contains provenance and parameters
        date = datetime.date.today()
        print("# Generated by GOATOOLS v{0} ({1})".format(goatools.__version__, date))
        print("# min_ratio={0} pval={1}".format(min_ratio, pval))