Feature/payouts

This adds ProjectPayouts.
Payouts are mostly a copy and paste job from what was in 1%. Simplified and adapted coding style to make it fitter better with the other Bluebottle apps.
Also see https://www.lucidchart.com/documents/edit/bd196f9e-0f9f-4f32-8cd0-94dd4fec5688

- Add bb_payouts and payouts apps.
- Add status Pending to orders.
- Use init_projects in most TestCases so all phases that payouts rely on are present.

These are doctests right? Do they also run from the test runner by default? Good thinking to use doctests for such simple helpers