[Merge] lp:~cjwatson/ubuntu-archive-publishing/parallel-germinate into lp:ubuntu-archive-publishing

[William Grant]

Review: Approve code

This should really use multiprocessing long-term, but it works for now.
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https://code.launchpad.net/~cjwatson/ubuntu-archive-publishing/parallel-germinate/+merge/222607
Your team Ubuntu Package Archive Administrators is requested to review the proposed merge of lp:~cjwatson/ubuntu-archive-publishing/parallel-germinate into lp:ubuntu-archive-publishing.