[Merge] ~nteodosio/update-manager:purgeidleloop into update-manager:main

[Nathan Teodosio]

I squashed, for organization's sake I did not keep Marco's clean up patch as a separate commit, opting to mention it in the commit message. I hope that is fine with you, Marco, let me know otherwise.
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https://code.launchpad.net/~nteodosio/update-manager/+git/update-manager/+merge/474755
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