Remove Jython code and documentation

[Andrey Martyanov]

It seems that ​https://docs.djangoproject.com/en/2.0/howto/jython/ is obsolete.

[Simon Charette]

At this point we don't support Jython at all given it's Py2k only.

[Tim Graham]

Rather than removing the document, I would add a note indicating that you must use Django 1.11 if you want to use Jython.

[Claude Paroz]

I don't think it's necessary to keep those docs. If we refer to older version of Django to use Jython, users can then refer to that version of the docs to find that document.

[Claude Paroz]

​PR

[Andrey Martyanov]

Replying to Claude Paroz:

I don't think it's necessary to keep those docs. If we refer to older version of Django to use Jython, users can then refer to that version of the docs to find that document.

Agreed.

[Tim Graham]

There was previous discussion about this where I gave the opinion that there's little advantage to removing Jython compatibility and documentation because when Jython releases a Python 3 version, we'll have to revert that commit and issue a new release to restore compatibility. At least if we leave things the way they are, there's a chance current Django releases may work with Jython 3.

[Claude Paroz]

There's no real traction currently for Jython 3, and that for several years now. Things can change, of course, but even if Jython 3 were to be released, this would probably need a new round of testing and adaptations.

[Tim Graham]

It's not the choice I would make, but I don't have any interest in Jython support and won't veto your decision. I think it's unfortunate to break any external links pointing to the dev version of docs/howto/jython.txt by removing that page.

[Claude Paroz]

I restored docs/howto/jython.txt with a simple header text. Could you review the wording?

[Claude Paroz]

In 23b21db3:

Fixed #28954 -- Removed Jython docs and specific code

Thanks Andrey Martyanov for the reporti, and Tim Graham for the review.

[Claude Paroz]

In 830636d:

[2.0.x] Fixed #28594 -- Removed Jython docs and specific code

Thanks Andrey Martyanov for the report, and Tim Graham for the review.
Backport of 23b21db31bfcf2a065d485617412cca43a311a4c from master.

[Carlton Gibson <carlton.gibson@…>]

In a2d894b2:

Refs #28954 -- Removed remaining Jython-specific code from dispatch tests.

Missed in 23b21db31bfcf2a065d485617412cca43a311a4c.

[Carlton Gibson <carlton.gibson@…>]

In d8b6a76b:

Refs #28954 -- Remove remaining Jython documentation.

There is still no further progress on Jython 3 since support for Jython
was stripped in Django 2.0. The developers experimenting with Jython 3
have stated that they would need to start from scratch, so it doesn't
look as though it will materialize for years to come.

Python 2 and Django 1.11, the last version to support Python 2.7, will
both be end-of-life before Django 3.1 is released. We should no longer
instruct users to use an unsupported version of Django.

[Carlton Gibson <carlton.gibson@…>]

In 08b426ae:

[3.0.x] Refs #28954 -- Remove remaining Jython documentation.

There is still no further progress on Jython 3 since support for Jython
was stripped in Django 2.0. The developers experimenting with Jython 3
have stated that they would need to start from scratch, so it doesn't
look as though it will materialize for years to come.

Python 2 and Django 1.11, the last version to support Python 2.7, will
both be end-of-life before Django 3.1 is released. We should no longer
instruct users to use an unsupported version of Django.

Backport of d8b6a76bc745b21c6cf2b29c220a91bcae7fd3d7 from master