cryptobyte: add support for UTCTIME values

[szank]

Hi, I have added support for UTC time, and a helper method that decodes time values regardless of the time tag used.

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[szank]

I signed it!

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CLAs look good, thanks!

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This PR (HEAD: 1d8c54a) has been imported to Gerrit for code review.

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This PR (HEAD: 6cf5e90) has been imported to Gerrit for code review.

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[gopherbot]

Message from Andrew Bonventre:

Patch Set 2: Run-TryBot+1 Code-Review+1

(1 comment)

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Patch Set 2:

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Patch Set 2: TryBot-Result+1

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Message from Andrew Bonventre:

Patch Set 2:

Also, does this require a crypto proposal at all? Will let Filippo weigh in.

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Next steps:
Within the next week or so, a maintainer will review your change and provide
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Most changes in the Go project go through a few rounds of revision. This can be
surprising to people new to the project. The careful, iterative review process
is our way of helping mentor contributors and ensuring that their contributions
have a lasting impact.

During May-July and Nov-Jan the Go project is in a code freeze, during which
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[gopherbot]

Message from Andrew Bonventre:

Patch Set 2: Run-TryBot+1 Code-Review+1

(1 comment)

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Message from Andrew Bonventre:

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Ping to original author of change.

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[gopherbot]

Message from Andrew Bonventre:

Patch Set 2:

Also, does this require a crypto proposal at all? Will let Filippo weigh in.

---

Please don’t reply on this GitHub thread. Visit golang.org/cl/98135.
After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from Gerrit User 5976:

Patch Set 1:

Congratulations on opening your first change. Thank you for your contribution!

Next steps:
Within the next week or so, a maintainer will review your change and provide
feedback. See https://golang.org/doc/contribute.html#review for more info and
tips to get your patch through code review.

Most changes in the Go project go through a few rounds of revision. This can be
surprising to people new to the project. The careful, iterative review process
is our way of helping mentor contributors and ensuring that their contributions
have a lasting impact.

During May-July and Nov-Jan the Go project is in a code freeze, during which
little code gets reviewed or merged. If a reviewer responds with a comment like
R=go1.11, it means that this CL will be reviewed as part of the next development
cycle. See https://golang.org/s/release for more details.

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[gopherbot]

Message from Andrew Bonventre:

Patch Set 2: Run-TryBot+1 Code-Review+1

(1 comment)

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[gopherbot]

Message from Andrew Bonventre:

Patch Set 2: -Run-TryBot -Code-Review

Ping to original author of change.

---

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After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from Andrew Bonventre:

Patch Set 2:

Also, does this require a crypto proposal at all? Will let Filippo weigh in.

---

Please don’t reply on this GitHub thread. Visit golang.org/cl/98135.
After addressing review feedback, remember to publish your drafts!