dhparam in default nginx can be optional for now

resource/nginx.cfg

@@ -14,7 +14,7 @@ server {
     ssl_certificate_key  ssl/postal.key;
 
     # Generate using: openssl dhparam 4096 -out /etc/ssl/dhparam.pem
-    ssl_dhparam /etc/ssl/dhparam.pem;
+    # ssl_dhparam /etc/ssl/dhparam.pem;
 
     ssl_protocols TLSv1.2 TLSv1.1 TLSv1;
     ssl_prefer_server_ciphers on;