Add Docs for Guidelines for Upgrading an Existing Project's Django

[Donald Stufft]

A decent addition to the docs would be a short page about the general process to go about replacing a projects version of django with a new one.

It would include any concerns/considerations that a developer should look at when doing the upgrade. One such thing is that starting with python 2.7, Deprecation warnings are silenced by default (the thinking being that end users don't care about them). So when upgrading Django you should use something like python -Wall manage.py test or python -Wd manage.py test to check for any warnings.

[Carl Meyer]

We already have a note about running with -Wall on the testing page, but that's not a place someone upgrading is likely to look. I think a short "Django upgrade checklist" page would be a good addition to the docs.

[anonymous]

I've attempted to resolve this ticket in my PR: ​https://github.com/django/django/pull/1012 Feel free to code review.

[Daniele Procida]

I have tentatively reserved this ticket for first-time committers who take part in the ​Don't be afraid to commit workshop at the ​DjangoCon Europe 2013 sprints on 18th and 19th May.

If you want to tackle this ticket before then, please don't let the fact that it's assigned to me stop you. Feel free to re-assign it to yourself and do whatever you like to it.

[Tim Graham]

Updated pull request (still needs some polish): ​https://github.com/django/django/pull/1173

[Tim Graham <timograham@…>]

In ef8a9bc7fafc394f2c413a6ad4057d67134d742b:

Fixed #17048 - Added docs for upgrading Django.

Thanks Donald Stufft for the suggestion and
Susan Tan and Brian Fabian Crain for the patch.

[Tim Graham <timograham@…>]

In 1add64684cef6877bf0faeb4a205be6ae07fc98e:

[1.5.x] Fixed #17048 - Added docs for upgrading Django.

Thanks Donald Stufft for the suggestion and
Susan Tan and Brian Fabian Crain for the patch.

Backport of ef8a9bc7fa from master.