tell clients not to cache their outer html

docs/example.nginx.conf

@@ -71,6 +71,9 @@ server {
     if ($args ~ ver=) {
         set $cacheControl max-age=31536000;
     }
+    if ($uri ~ ^/.*(\/|\.html)$) {
+        set $cacheControl no-cache;
+    }
     # Will not set any header if it is emptystring
     add_header Cache-Control $cacheControl;