Removed tests for django.utils.unittest vs. unittest.

Silenced warnings caused by the deprecation of django.utils.unittest.

Thanks Preston Timmons and Carl Meyer for their advice.

Fixed #20680.
This doesn't need to be a package any more.

Refs #20680.
Fixed a few more imports of django.utils.unittest.

One import per line please! Refs #20680.
Deprecated django.utils.dictconfig.

The module still exists for whoever uses it in its current state, but it
isn't imported by Django anywhere.
Reflected the new default value of LOGGING_CONFIG in docs.
Relied on NullHandler from the logging stdlib module.
Merge branch 'master' into schema-alteration
Fix M2M interaction with transactions
Add unique_together altering operation
Autodetection of unique_together changes
Support for index_together in schema backends
Fix combined alters on PostgreSQL
Fix some bad test running under PostgreSQL
Fix get_constraints to do multi-column indexes properly on pg
Fix index_together test
Fix "semicolon" in docs
Add AlterIndexTogether operation
Make get_constraints return columns in order
Merge pull request #1321 from bfirsh/semicolon-colon-docs

Fix "semicolon" in form docs
A couple more semicolon -> colon fixes; refs #18134.