Fix example to return Response object

Author: igorw

example.php

@@ -14,7 +14,8 @@
  }
 
  $params = $token->getExtraParams();
- return sprintf('Welcome @%s!', $params['screen_name']);
+ $body = sprintf('Welcome @%s!', $params['screen_name']);
+ return new Response($body);
 });
 
 $stack = (new Stack\Builder())