fix namespaces and references

src/Api/Controllers/V1/UsersController.php

@@ -1,16 +1,10 @@
 <?php
-namespace Controllers;
+namespace Api\Controllers\v1;
 
-use Core\Request;
-use Core\Response;
+use Api\Core\Request;
+use Api\Core\Response;
 
 class UsersController {
-    private $externalService;
-
-    public function __construct(\Services\ExternalApiService $externalService) {
-        $this->externalService = $externalService;
-    }
-
     public function index(Request $req, Response $res) {
         return $res->json([
             'users' => ['Mario', 'Luigi']