Publish typescript typings to npm

[rifler]

fixes #375

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[rifler]

i have to install yarn...

[kristoferbaxter]

This project uses https://volta.sh/ to manage this, sorry for the confusion!

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We found a Contributor License Agreement for you (the sender of this pull request), but were unable to find agreements for all the commit author(s) or Co-authors. If you authored these, maybe you used a different email address in the git commits than was used to sign the CLA (login here to double check)? If these were authored by someone else, then they will need to sign a CLA as well, and confirm that they're okay with these being contributed to Google.
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A Googler has manually verified that the CLAs look good.

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[kristoferbaxter]

Manually verified CLA, issue caused by force pushes.

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We found a Contributor License Agreement for you (the sender of this pull request), but were unable to find agreements for all the commit author(s) or Co-authors. If you authored these, maybe you used a different email address in the git commits than was used to sign the CLA (login here to double check)? If these were authored by someone else, then they will need to sign a CLA as well, and confirm that they're okay with these being contributed to Google.
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[googlebot]

A Googler has manually verified that the CLAs look good.

(Googler, please make sure the reason for overriding the CLA status is clearly documented in these comments.)

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[kristoferbaxter]

Looks good, thank you for the contribution!