When django.setup() (and then configure_logging) is called inside
catch_warnings, logging setup is negatively affected (notably
warnings.showwarning definition).

Django determines automatically which application models belong to,
provided the application can be imported without importing models.

Refs #21018, #21688.

Refs #12288, #21679.

This was used for python 2.6 and unittest2 compatibility. It was
forgotten when the code that used it was removed.

Added test to verify an empty label performs discovery on the current
working directory.

Used abstract inheritance to cut down on code repetition.

Disqus regularly does 40-50k/s

When STATIC_ROOT wasn't set, collectstatic --clear would delete
every files within the current directory and its descendants.

This patch makes the following changes:

Prevent collectstatic from running if STATIC_ROOT isn't set.

Fixed an issue that prevented collectstatic from displaying the
destination directory.

Changed the warning header to notify when the command is run
in dry-run mode.

Thanks Aymeric Augustin for the report and the review.

Thanks Jannis and Marc for the feedback.

Fixed #21717.

Fixed #21679.

Fixed #21683.

This check will miss duplicates until the check for duplicate labels is
added.

Refs #21679.

It doesn't account for app configs.

Refs #21679.

Thanks Marco Badan for the report.

Thanks ken.nelson at maclaren.com.

Fixed #21715.

Thanks Anssi for noticing this mistake in a refactoring.

Thanks cjerdonek for the suggestion.

This avoids duplicating code.

To resolve the conflict between application names.

Now that the refactorings are complete, it isn't particularly useful any
more, nor very well named. Let's keep the API as simple as possible.

Fixed #21689.

Many thanks to @bitdancer and @aaugustin for answering my stupid questions about (mail)encodings and pointing me in the right direction.

Thanks ashley at ashleymills.com for the suggestion.

Changed console and filebackend to use msg.as_bytes to output the data as it would get send via smtp.