Fix tutorial's step 1 for Python 3

Merge branch 'nullbooleanfield_testcase' of git://github.com/dpetzel/django-rest-framework into dpetzel-nullbooleanfield_testcase

Conflicts:
	rest_framework/tests/test_serializer.py

Fix infered field type for models.NullBooleanField

Fix nested serializers with renamed fields

Merge branch 'master' of git://github.com/philipforget/django-rest-framework into philipforget-master

Add notes on lookup_prefix argument and why it's there even though unused by the default implementations.

'lookup_prefix' on SimpleRouter.get_lookup_regex, easing code de-duplication

Fix default values always being False for browsable API

This fixes a bug that was introduced in 28ff6fb1 [1] for the
browsable API, specifically with how it handled default values
for boolean fields.  Previously, it had a global default for
boolean fields set to `False`, which was different than the
standard None that was used elsewhere.  Because this only needed
to be done for the browsable API, a fix was put into place that
only set the default to `False` when form data was passed into
the serializer.  This had the unintended side effect of overriding
any default set on the boolean field.

This fixes #1101 [2] by only overriding the default if the default is
`None`, which is the default for all fields.

[1]: https://github.com/tomchristie/django-rest-framework/commit/28ff6fb1ec02b7a04c4a0db54885f3735b6dd43f
[2]: https://github.com/tomchristie/django-rest-framework/issues/1101

Fixed the nested model serializers in case of the related_name isn’t set...

Conflicts:
	docs/api-guide/routers.md

third-party package: wq.db

Add required imports to Generating Tokens example, and update with get_user_model()

Because that's a better way of doing it.

Previously we were missing User and post_save.

Update routers.md

Reference to ```DefaultRouter``` should be ```SimpleRouter```

This allows @alanjds/drf-nested-routers to not duplicate/monkeypatch work made here

Refine model manager behavior so as not to use the behavior in incorrect...