[Merge] lp:~mvo/ubuntu/vivid/ubuntu-core-upgrader/add-test-tar-generator into lp:ubuntu/ubuntu-core-upgrader

[James Hunt]

Review: Approve

Looks good as a start.

As mentioned, unfortunate that we were both working on the same code at the same time, but I can rework my code again to fit in with what we have here. Note that I had solved the options issue by passing a dict of options to the Upgrader() rather than an argparse Namespace() object.
-- 
https://code.launchpad.net/~mvo/ubuntu/vivid/ubuntu-core-upgrader/add-test-tar-generator/+merge/251230
Your team Ubuntu branches is requested to review the proposed merge of lp:~mvo/ubuntu/vivid/ubuntu-core-upgrader/add-test-tar-generator into lp:ubuntu/ubuntu-core-upgrader.