Implemented oauth. Closes #38.
Replaced db with ndb. Closes #46.

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Squash commit from https://github.com/ndahlquist/whaler/pull/50 created by Whaler.
Generalize interstitial endpoint.

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Squash commit from https://github.com/ndahlquist/whaler/pull/51 created by Whaler.
Added a few comments.

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Squash commit from https://github.com/ndahlquist/whaler/pull/52 created by Whaler.
Authenticate calls to /queue_merge. Closes #48.

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Squash commit from https://github.com/ndahlquist/whaler/pull/53 created by Whaler.
Added update message for users on old versions.

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Squash commit from https://github.com/ndahlquist/whaler/pull/55 created by Whaler.