Merge branch 'easily-add-new-formset-to-product-update-page' into machtfit

* branch easily-add-new-formset-to-product-update-page:
  Make it trivially easy to add more formsets to the product update page
  Unify __init__ method signature of formset classes
  customize FormSet class after calling inlineformset_factory
  Whitespace, Formatting, PEP8
Merge branch 'origin/issue/1002/pbd_stockrecords' into machtfit

* branch origin/issue/1002/pbd_stockrecords:
  Pre-select partner if appropriate
  Pass user into StockRecordForm
  PBD: Enforce one stock record matching users partners

Force the partner to be the partner of the user when creating and editing stockrecords

Conflicts:
	oscar/apps/dashboard/catalogue/forms.py
	oscar/apps/dashboard/catalogue/views.py