[Distutils] TLS support policy & PyPI communications

[Sumana Harihareswara]

PSF blogged last year
https://pyfound.blogspot.com/2017/01/time-to-upgrade-your-python-tls-v12.html
that

> The more crucial deadline comes June 30, 2018. On that date all remaining python.org sites, including PyPI, will no longer support TSL 1.0 and 1.1. Older Python versions that do not implement TLSv1.2 will be prohibited from accessing PyPI.

I asked Ernest W. Durbin III whether I ought to re-announce this to
users in my PyPI announcements. He looked at our TLS trends/stats and
told me we have a very very low proportion of traffic that will be
affected when we shift over. Therefore, since it'll affect so few, I
won't shout about TLS versions in my PyPI communications. Marking that
here for the record.

-- 
Sumana Harihareswara
Changeset Consulting
https://changeset.nyc