Misc/NEWS.d/next/Library/2018-01-21-15-01-50.bpo-31453.cZiZBe.rst

Add TLSVersion constants and SSLContext.maximum_version / minimum_version
attributes. The new API wraps OpenSSL 1.1
https://www.openssl.org/docs/man1.1.0/ssl/SSL_CTX_set_min_proto_version.html
feature.