groovy.py parsing depends on sre internals and does not work for Python 3.6

[myukselen]

Used functionality is not exposed by sre_parse. As a work around version based implementation might be done in Scanner._get_group_pattern() function such as

        for phrase, action in self.lexicon:
            if sys.version_info >= (3, 6):  # internal representation changed in 3.6, add_flags del_flags are given 0
                patterns.append(sre_parse.SubPattern(sub_pattern, [
                    (SUBPATTERN, (len(patterns) + 1, 0, 0, sre_parse.parse(phrase, flags))), ]))
            else:
                patterns.append(sre_parse.SubPattern(sub_pattern, [
                    (SUBPATTERN, (len(patterns) + 1
                                  , sre_parse.parse(phrase, flags))),
                ]))