Fixed #22380 -- Missing SECRET_KEY variable in sample settings file for testing
Merge pull request #2514 from vlal/ticket_22380

Fixed #22380 -- Missing SECRET_KEY variable in sample settings file for ...
Fixed case in form widgets docs
Fixed #21649 -- Added optional invalidation of sessions when user password changes.

Thanks Paul McMillan, Aymeric Augustin, and Erik Romijn for reviews.
Fixed #22236 -- Removed inappropriate usage of signals

Thanks Aymeric Augustin for the report and Tim Graham for the review.
Fixed #22216 -- Added Form.non_field_errors to form API doc.
Fixed #21977 -- Deprecated SimpleTestCase.urls
Removed casting to bool just before negation.
Fixed #21084 -- Used proxy model's content type for admin log entries.
Fixed #21084 -- Used proxy model's content type for admin log entries.

(the previous commit included only the test)
Added missing request parameter to get_current_site().
Fixed #22405 -- Fixed string error in models/queries docs.
Fixed #9535 -- Added a reference guide for file upload classes.
Fixed some spelling issues in docs.
Added Python 3.4 to list of supported version in docs/intro/install.txt
Fixed #16205 -- Added an installation for Windows.
Refs #21230 -- removed direct settings manipulation from signed cookies tests
Fixed #13408 -- Deprecated silent unpacking exception passing in for template tag.

Thanks peterbe for the suggestion.
Fixed small typo in django-admin.txt

The word 'by' seemed to be missing from the first line of the compilemessages command.
Noted that pip is included with Python 3.4 in Windows install guide.

Thanks CHI Cheng.