Merge branch 'patch-2' into 'develop'

* fix nginx 1.15 warning:

See merge request pleroma/pleroma!213

installation/pleroma.nginx

@@ -29,7 +29,6 @@ ssl_session_cache shared:ssl_session_cache:10m;
 
 server {
     listen 443 ssl http2;
-    ssl on;
     ssl_session_timeout 5m;
 
     ssl_trusted_certificate   /etc/letsencrypt/live/example.tld/fullchain.pem;