docs: improve sample code format

Author: kenjis

user_guide_src/source/installation/upgrade_routing/001.php

@@ -2,14 +2,13 @@
 
 namespace Config;
 
-// Create a new instance of our RouteCollection class.
-$routes = Services::routes();
+// ...
 
-// Load the system's routing file first, so that the app and ENVIRONMENT
-// can override as needed.
-if (file_exists(SYSTEMPATH . 'Config/Routes.php')) {
-    require SYSTEMPATH . 'Config/Routes.php';
-}
+/*
+ * --------------------------------------------------------------------
+ * Route Definitions
+ * --------------------------------------------------------------------
+ */
 
 // ...
 
@@ -22,3 +21,5 @@
 $routes->add('drivers/create', 'Drivers::create');
 $routes->add('drivers/update', 'Drivers::update');
 $routes->add('posts/(:segment)', 'Posts::view/$1');
+
+// ...

user_guide_src/source/installation/upgrade_routing/ci3sample/001.php

@@ -1,12 +1,14 @@
 <?php
 defined('BASEPATH') OR exit('No direct script access allowed');
 
-$route['posts/index'] = 'posts/index';
+// ...
+
+$route['posts/index']  = 'posts/index';
 $route['teams/create'] = 'teams/create';
 $route['teams/update'] = 'teams/update';
 
-$route['posts/create'] = 'posts/create';
-$route['posts/update'] = 'posts/update';
+$route['posts/create']   = 'posts/create';
+$route['posts/update']   = 'posts/update';
 $route['drivers/create'] = 'drivers/create';
 $route['drivers/update'] = 'drivers/update';
-$route['posts/(:any)'] = 'posts/view/$1';
+$route['posts/(:any)']   = 'posts/view/$1';