Merge pull request #624 from code-dot-org/staging

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Merge pull request #625 from code-dot-org/staging

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Merge pull request #629 from code-dot-org/staging

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Merge pull request #631 from code-dot-org/staging

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Merge pull request #633 from code-dot-org/test

DTP
Identify front-ends that fail to update in RED and take them out of rotation automatically.
Merge branch 'test' of github.com:code-dot-org/code-dot-org into staging