This allows updating code in both places, if necessary. Getting Django
1.5 support would be painful otherwise. This also removes the circular
dependency of django-oscar-testsupport on Oscar.

The requirements were merged. The imports were updated
accordingly. Unused imports in the touched files were removed. No
further changes.

* Emailbackend: Updated to use REQUIRED_FIELDS
* Demo and sandbox site now use compat.AUTH_USER_MODEL as well
* Added example custom user that gets tested for Django >= 1.5

This is required to allow the pages component of the dashboard to
continue to work correctly.

* Tidy implementation of validator
* Tests improved and moved to tests/integration (as they call resolve
  internally)

Change to required address fields was causing the shipping address step
to fail.

When adding to the basket, products with options were treated as
different products for each combination of options. This allowed adding
more products into the basket than are available for purchase.

The handling has been updated to sum up the already added quantity of
the product regardless of options.

Fixes #665

This is required for multiprocess testing to work (eg ./runtests.py
--processes=2)

Fixes #614

As they save stuff...

We now check in the OrderCreator for this attribute and only allocate if
it is true.

Fixes #671

Without a value, applying an AbsoluteBenefit raises a TypeError.

Fixes #670

This change introduces a templatetag which assigns context for adding a
'back to search results' link to a product detail page.  This can be
useful for certain types of user (who don't use the back button) and
want to get back to their, possibly complicated, set of search filters.

Fixes #456

The auth backend now gracefully handles situations where there are users
with the same email address.

Introduced in 7fd62f2af0.

The clean method was raising a KeyError when the date fields were empty.

The profile test can_change_password checked if the password change
form can be submitted succesfully, but did not verify that Django's
authentication system accepts the new password.

Product updates in the dashboard weren't being saved. This was a
regression introduced by my refactoring of the ProductUpdate/Create
views.

A test to ensure that a product title does indeed get updated has been
added.

Reported and fix supplied by @soloweb in #613. Thank you.

OSCAR_REQUIRED_ADDRESS_FIELDS allows setting which fields are required.
The use case is that post codes are expected to be required, but many
countries don't actually use them.

* Doesn't use progressive plugin on travis (which made the console
  output unreadable).
* Allows arbitrary nose options to be used with ./runtests.py.  Before,
  they might get clobbered.
* Avoid dupliation issue with nose picking up options independentally
  from the testrunner script

Default behaviour is still the same.

This change applies the discount to all matching lines in the benefit
range, weighting the discount by the line prices.  The old way was to
iterate over each line and try and apply all the discount.

This new way means that applying an absolute benefit consumes more
products from the basket than the old way, which may possibly have some
confusing side-effects.

This change avoids an issue where customers can get a free product if
they return most of the ordered products apart from the one that was
discounted to zero.

They aren't treated specially any more.  They become part of the
'applications' collection rather than being attached to the basket.

This paves the way for custom benefits to return successful applications
that don't lead to a discount.

By adding the __setstate__ method an infinite loop is avoided regarding
the use of __getattr__ on the ProductAttributesContainer model.

Moving tests into appropriate folder

So stopwords can be moved from slugs

...as they are all integration tests (they save stuff).

This uses the unidecode package to convert non-ASCII words to ASCII
equivalents.  We use a new slugify function to wrap this logic as we
will want to use it elsewhere.

See this StackOverflow thread for context:
http://stackoverflow.com/questions/702337/how-to-make-django-slugify-work-properly-with-unicode-strings/

Unidecode becomes a new dependency for Oscar.
https://pypi.python.org/pypi/Unidecode

Hat-tip to @avsazonov for suggesting this fix.

New impl is considerably simpler and lets the save method update each
node's slug and full name.