[1.4.X] Fixed #19506 - Remove 'mysite' prefix in model example.

Thanks Mike O'Connor for the report.

Backport of 52a2588df6 from master
[1.4.x] Addeded CSS to bold deprecation notices.

Thanks Sam Lai for mentioning this on the mailing list.

Backport of 227bd3f8db from master
[1.4.x] Fixed #19555 - Removed '2012' from tutorial 1.

Thanks rodrigorosa.lg and others for the report.

Backport of 99315f709e from master
[1.4.x] Fixed #18144 -- Added backwards compatibility with old unsalted MD5 passwords

Thanks apreobrazhensky at gmail.com for the report.
Backport of 63d6a50dd from master.
[1.5.x] Lowered field ordering requirement in ogrinspect test

This test was randomly failing depending on the library environment.
Backport of a1c470a6f from master.
[1.4.x] Fixed #19702 -- Changed a SQL command syntax to be MySQL 4-compatible

Thanks matf at op.pl for the report.
[1.4.x] Fixed #19756 - Corrected a ManyToMany example and added some links and markup.

Backport of 43efefae69 from master
[1.4.x] Fixed #19645 -- Added tests for TransactionMiddleware

Backpatch of f556df90be995a83b979cf875705d98521ab4dc7. Backpatching
these tests so that it will be easier to backpatch the fix for #19707.
[1.4.x] Fixed #19707 -- Reset transaction state after requests

Backpatch of a4e97cf315142e61bb4bc3ed8259b95d8586d09c.
[1.4.x] Made custom m2m fields without through easier to use

The change in f105fbe52b21da206bfbaedf0e92326667d7b2d4 made through=None
m2m fields fail in cases where they worked before. It isn't possible to
create such fields using public APIs. The fix is trivial, so it seems
worth fixing this for custom m2m field users.

This is not a backport from master. Master has gotten enough other
changes to related fields internal API that this fix alone isn't enough
to do any good.
Fixed WSGIPythonPath instruction in deployment docs

Partial backport of 3abf6105b6 from master. Refs #19042.
[1.4.x] Removed try-except in django.db.close_connection()

The reason was that the except clause needed to remove a connection
from the django.db.connections dict, but other parts of Django do not
expect this to happen. In addition the except clause was silently
swallowing the exception messages.

Refs #19707, special thanks to Carl Meyer for pointing out that this
approach should be taken.
[1.4.x] Fixed #19815 - Removed an unused import in tutorial 3.

Thanks pedro.calcao@ for the report.