docs, various fixes and certbot-cloudflare example

confs/site/main-lua.conf

@@ -7,6 +7,11 @@ set $session_check_addr on;
 
 access_by_lua_block {
 
+-- disable checks for internal requests
+if ngx.req.is_internal() then
+	return
+end
+
 -- let's encrypt
 local use_lets_encrypt		= {% if AUTO_LETS_ENCRYPT == "yes" %}true{% else %}false{% endif %}