docs: add routing for Upload sample code

Author: kenjis

user_guide_src/source/libraries/uploaded_files.rst

@@ -81,6 +81,13 @@ this code and save it to your **app/Controllers/** directory:
     only :ref:`rules-for-file-uploads` can be used to validate upload file with :doc:`validation`.
     The rule ``required`` also can't be used, so use ``uploaded`` instead.
 
+The Routes
+==========
+
+Using a text editor, open **app/Config/Routes.php**. In it, add the following two routes:
+
+.. literalinclude:: uploaded_files/021.php
+
 The Upload Directory
 ====================
 

user_guide_src/source/libraries/uploaded_files/021.php

@@ -0,0 +1,18 @@
+<?php
+
+// ...
+
+/*
+ * --------------------------------------------------------------------
+ * Route Definitions
+ * --------------------------------------------------------------------
+ */
+
+// We get a performance increase by specifying the default
+// route since we don't have to scan directories.
+$routes->get('/', 'Home::index');
+
+$routes->get('upload', 'Upload::index');          // Add this line.
+$routes->post('upload/upload', 'Upload::upload'); // Add this line.
+
+// ...