[Merge] ~enr0n/ubuntu-release-upgrader:lp2020406 into ubuntu-release-upgrader:ubuntu/main

[Nick Rosbrook]

Review: Disapprove

We no longer think this approach makes sense, so I do not plan on working on this further.
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https://code.launchpad.net/~enr0n/ubuntu-release-upgrader/+git/ubuntu-release-upgrader/+merge/445212
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