Contribution checklist v2

[Florian Weimer]

* Joseph Myers:

> On Tue, 8 Oct 2019, Gabriel F. T. Gomes wrote:
>
>> Yes, that sounds really good to me and I wonder if we shouldn't stop
>> writing ChangeLogs now, because the ChangeLogs we write in this cycle will
>> likely be overwritten by the output of gitlog_to_changelog.py (I'm not
>> sure if that's what people here had in mind, but I would be happy with
>> this approach).
>
> The point at which we stop writing ChangeLogs should be exactly the point 
> at which the ChangeLog file is renamed to ChangeLog.old/ChangeLog.19.

I think we need to fix some whitespace issues first:

  <https://sourceware.org/ml/libc-alpha/2019-10/msg00132.html>

At least my local commit hook rejected the move without that change.

Thanks,
Florian