This is a preparatory commit for using isort for sorting all of our
imports, merging changes to files where we can easily review the
changes as something we're happy with.
These are also files with relatively little active development, which
means we don't expect much merge conflict risk from these changes.
This is a major rewrite of the billing system. It moves subscription
information off of stripe Subscriptions and into a local CustomerPlan
table.
To keep this manageable, it leaves several things unimplemented
(downgrading, etc), and a variety of other TODOs in the code. There are also
some known regressions, e.g. error-handling on /upgrade is broken.
A lot of the seemingly unrelated test fixture changes are because we're
removing a query to stripe in the upgrade path, in cases when the user's
realm has an existing Customer object.
Tim Abbott
Rishi Gupta
Vishnu Ks