RFC 3164 parser failed to parse UTC time

[imhuai]

Hi, I think that both of following time strings are valid RFC3339 time format. However, RFC3164 parser is not able to parse the second type of timestamp (i.e. 2019-11-06T08:12:25Z) due to the expected parsing length of RFC3339 is limited to 25. Thank you.

2019-11-06T08:12:25+08:00 // length: 25
2019-11-06T08:12:25Z // UTC time, length: 20

[itd-mathe]

the bug is still not fixed! Why is the Go standard library time.Parse not used in the module?
The further consequence of this error is that the TAG is ignored. It cost me quite some time in debugging...