We only needed it because Django 1.4 shipped with a pretty old version
of six. Support for that has been removed, and Django 1.5 ships with six
1.6.1, which is more current than we required.

This nicely avoids an issue with django-extra-views pinning a six
version which caused the sandbox build to fail:
https://travis-ci.org/tangentlabs/django-oscar/jobs/32223978#L971

My fix in 5f23648 forgot to change the receiver registration in the app
config.
Also removed an unused import, and a deprecation warning in the tests.

PR #1447 was by a first-time committer, so I did not want to rewrite
the commits.

* Removed accidentally committed file
* Style fixes

Closes #1447.

This commit is the squashed, but unchanged version of #1447. It adds an
__eq__ method to prices to be able to check them for equality.

This commit adds the python_2_unicode_compatible decorator to all models
that define a text representation. Furthermore, it adds a test to ensure
that we never forget to do that.

It is explained in details in the Django docs:
https://docs.djangoproject.com/en/dev/topics/python3/#str-and-unicode-methods

A custom app needs to inherit from Oscar's app config. This ensures the
correct app label, and that any startup code (receivers, etc.) is
executed.
Per the camp ground rule, the fork_app command has been slightly
refactored.

This hopefully prevents me from missing more.

I think the Oscar upgrade/forking process for forked apps will get
simpler with the new migrations. One probably will be able to just fake
an initial migration, or something like that. But for now, copying
them across as we did before should be a safe bet.

Otherwise Django 1.7 rightly complains about duplicate app labels.

South isn't supported in Django 1.7 and upwards, so we can only skip
them.

The ``permissions_required`` decorator, and hence
``Application.permissions_map`` and
``Application.default_permissions``, now
handle both methods and properties on the User model. Previously, it
wasn't supported, but a docstring showed ``is_anonymous`` as an example,
which is a method.

I presume filter returns an iterator in Python 3.

Importing things in settings is discouraged. But until now,
OSCAR_SLUG_FUNCTION could only be set as a callable, which requires
importing. It's now been updated to use the import_string function.

We ship some apps, e.g. search, without models.py. I think that
means it is not a valid Django app for Django < 1.7. But either way,
Django 1.7 definitely allows apps without models.py, so we need to
ensure we do the right thing.

Otherwise the ModelAdmins aren't discovered.

This makes it easier to customise Oscar. You can run this command to
quickly create local versions of an app that you want to customise. The
command creates the appropriate folder, __init__.py and models.py. The
only step requiring human intervention is to modify INSTALLED_APPS to
include the new app package.

Duplicate migration numbers can happen when merging changes from
different branches. This test ensures that we address the issue right
away.

This required extending the UnicodeCSVWriter to be able to deal with
file-like objects as well. This is used to create downloadable CSV files
in memory.

TestCase.assertEquals (note the s at the end) has been deprecated.
The only failing tests remaining are CSV related, which is not
surprising.

Tests for separator and uppercase options.

Taken from django-extensions with some adapting to our needs.

New migrations need to be manually updated to correctly deal with custom
user models. This test fails if this isn't done.

This should always be used instead of Django's silent version.

This reverts fa1f8403 which moved them from models.py to __init__.py.
As reported by @mvantellingen, importing receivers from __init__.py
breaks the way models are normally overridden as it causes the core
models.py to get imported before the custom one.

We need to move back to the old system and will need to advise that the
debug toolbar needs to be set-up explicitly to avoid circular import
issues with models.

Fixes #1159
Original issue #1125

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

Fixes #614

So stopwords can be moved from slugs