Also added tests with pytz and removed misplaced tests.

Also added tests for is/make_aware/naive.

Thanks Tom Michaelis for the report.

Authorization backends can now raise PermissionDenied in "has_perm"
and "has_module_perms" to short-circuit authorization process.

Clarified the explanation on the order in which user provided variables
to render_to_response, RequestContext and context processors are
loaded.

Now this method is only called only if the object is an instance.
This allows to have field classes as model class attributes.

This is the default now, see https://bitbucket.org/pypa/wheel/commits/c29f82b4cf76df71f8d55b0f825af6063d3b9892

While Node class has a useful `__str__`, its `__repr__` is not that
useful. Added a `__repr__` that makes use of the current `__str__`.
This is especially useful since the more popular `Q` class inherits
`tree.Node`. Also created new tests that cover most of `Node` class
functionality.

It was previously used in a test that was deprecated and then removed, this cruft can be removed now.

Thanks to Claude Paroz for the report and patch and Tomasz
Paczkowski for the review.

Forwardport of 79f15ab1 from stable/1.7.x

cater for running tests from another directory than tests

cater for running tests from another directory than tests - applying existing pattern to newly added test_testcase_ordering as well

Thanks nikolay.v.golub@gmail.com for the report.

Added DateTimeCheckMixin to avoid the use of default, auto_now, and
auto_now_add options together. Added the fields.E151 Error that is raised
if one or more of these options are used together.

In django.db.backends.BaseDatabaseWrapper, pulled the creation of
cursors in the non-debug case into a separate method, in order to
make behavior more consistent when overriding the cursor creation
in derived classes.

Thanks Stephen Burrows for work on the patch as well.

Forwardport of 2914f669 from stable/1.7.x

Fix typo that disabled code example highlighting

typo: urlaprse -> urlparse

This is a security fix. Disclosure following shortly.

This is a security fix. Disclosure following shortly.

Fields can now receive the `label_suffix` attribute, which will override
a form's `label_suffix`.

This enhances the possibility to customize form's `label_suffix`, allowing
to use such customizations while using shortcuts such as
`{{ form.as_p }}`.

Note that the field's own customization can be overridden at runtime by
using the `label_prefix` parameter to `BoundField.label_tag()`.

Refs #18134.

Thanks ewjoachim for the sugggestion.