WIP implement payment fsm and signals BOOK-741
- update migrations to work with custom model classes
- start work on intgrating docdata with payments BOOK-741
- cleaned up some of the payment signals
WIP get docdata response to update payment status BOOK-717 BOOK-741
add debug logging BOOK-741
remove fascade reference
use docdata test setting when connecting with client BOOK-717
no need to pass if we save
remove pass for status change methods
remove pass for status change methods
Merge remote-tracking branch 'origin/feature/fund-loving-criminals' into feature/book-741

Conflicts:
	bluebottle/payments_docdata/adapters.py
	bluebottle/payments_docdata/gateway.py
	bluebottle/payments_docdata/views.py
update migrations for payments docdata
skip pre_save unless Payment BOOK-741
add some packages for testing and docdata
Merge branch 'feature/book-741' of github.com:onepercentclub/bluebottle into feature/book-741
update signals to use connect method in each class extending Payment and update the docdata tests to stub the docdata remote request (test is correctly failing) BOOK-741
move signal connects for payment status changes to the model file and fix tests
fix view code broken in previous bad merge
use fsm methods on order model to change status
refactor fsm test helpers into new class and add more tests for payments
Merge branch 'feature/book-741' into feature/BOOK-719

Conflicts:
	bluebottle/payments/models.py
	bluebottle/payments_docdata/adapters.py
	bluebottle/payments_docdata/models.py
	test_requirements.txt