In the wiki you see the following to register exception responses, this seems to be specific for lumen. Where and how to I do this in a laravel 5.2 installation.
app('Dingo\Api\Exception\Handler')->register(function (Symfony\Component\HttpKernel\Exception\UnauthorizedHttpException $exception) {
    return Response::make(['error' => 'Hey, what do you think you are doing!?'], 401);
});