Upgrade OpenSSL to 1.1
OpenSSL 1.1.0 is binary compatible with OpenSSL 1.1.1 that will be the next LTS.
The new LTS comes with TLS 1.3, ChaCha20-Poly1305, x25519 and many other goodies.
Since many packages depends on it, it would be great to have an integration branch to test the upgrade.
https://www.openssl.org/policies/releasestrat.html
(from redmine: issue id 8998, created on 2018-06-13)