v1 -> v2 migration tests

[Daniel Axtens]

Hi all,

I am running tests of v1 to v2 migrations. The origin is
v1.patchwork.dja.id.au and the destination is
migrate.patchwork.dja.id.au.

Every hour, data is synced from 'v1' to 'migrate' - emails are only
ingested in v1.

I haven't seen any _obvious_ issues, but please do check it out.

Please continue to test things, including your API clients. (Obviously
events won't work!) Users created in v1 should exist in migrate (after
the hourly sync).

Regards,
Daniel