don't include ssl config by default

If the server has no ssl config - there's no need to load a config file
full of ssl config

nginx.conf

@@ -118,7 +118,5 @@ http {
   # a specific directory, or on an individual server{} level.
   # gzip_static on;
 
-  include h5bp/directive-only/ssl.conf;
-
   include sites-enabled/*;
 }