BUG accept and deprecate negative integer for max_colwidth

[glemaitre]

• closes BUG display.max_colwidth do not accept -1 for unlimited width #31532
• tests added / passed
• passes black pandas
• passes git diff upstream/master -u -- "*.py" | flake8 --diff
• whatsnew entry

[glemaitre]

Do you have an entry point in the documentation to add the removal of support for version 1.2, to ease the maintanance on your side?

[glemaitre]

So from the tests failing it seems is_nonnegative_int will handle None while is_int will not.
It seems a bit surprising at first. @jorisvandenbossche would it make sense that they behave the same? Probably this just an internal function anyway.

[jreback]

looks good, ping when revised and green (also merge master).

[jreback]

lgtm. ping on green.

[glemaitre]

ping @jreback it's green :)

[lumberbot-app]

Owee, I'm MrMeeseeks, Look at me.

There seem to be a conflict, please backport manually. Here are approximate instructions:

1. Checkout backport branch and update it.

$ git checkout 1.0.x
$ git pull

2. Cherry pick the first parent branch of the this PR on top of the older branch:

$ git cherry-pick -m1 8dfb54967a935562e3379f999a696fdd1b4ba545

3. You will likely have some merge/cherry-pick conflict here, fix them and commit:

$ git commit -am 'Backport PR #31569: BUG accept and deprecate negative integer for max_colwidth'

4. Push to a named branch :

git push YOURFORK 1.0.x:auto-backport-of-pr-31569-on-1.0.x

5. Create a PR against branch 1.0.x, I would have named this PR:

"Backport PR #31569 on branch 1.0.x"

And apply the correct labels and milestones.

Congratulation you did some good work ! Hopefully your backport PR will be tested by the continuous integration and merged soon!

If these instruction are inaccurate, feel free to suggest an improvement.

[jreback]

thanks @glemaitre

[jreback]

@glemaitre if u want to do the manual back port above would be great

[glemaitre]

I'll do that.