Merge pull request pallets#1456 from jonafato/proxy-setup-x-forwarded-proto

Add X-Forwarded-Proto header to proxy setup example docs

Author: untitaker

docs/deploying/wsgi-standalone.rst

@@ -97,9 +97,10 @@ localhost at port 8000, setting appropriate headers:
             proxy_pass         http://127.0.0.1:8000/;
             proxy_redirect     off;
 
-            proxy_set_header   Host             $host;
-            proxy_set_header   X-Real-IP        $remote_addr;
-            proxy_set_header   X-Forwarded-For  $proxy_add_x_forwarded_for;
+            proxy_set_header   Host                 $host;
+            proxy_set_header   X-Real-IP            $remote_addr;
+            proxy_set_header   X-Forwarded-For      $proxy_add_x_forwarded_for;
+            proxy_set_header   X-Forwarded-Proto    $scheme;
         }
     }