title: tcpdf on Lumen Class 'PDF' not found
body: <p>I created a new project with Lumen 5.4.7 and I added the TCPDF library from <code>elibyy/tcpdf-laravel</code> version 5.4.2 (with Lumen support):</p>
  
  <pre><code>composer require elibyy/tcpdf-laravel "5.4.2"
  </code></pre>
  
  <p>I enabled the Facades and Service Provider in <code>bootstrap/app.php</code> with</p>
  
  <pre><code>$app-&gt;withFacades();
  $app-&gt;register(Elibyy\TCPDF\ServiceProvider::class);
  </code></pre>
  
  <p>And I created a basic Controller:</p>
  
  <pre><code>&lt;?php
  
  namespace App\Http\Controllers;
  use \PDF;
  
  class PdfController extends Controller
  {
      /**
       * Create a test PDF file.
       *
       * @return void
       */
      public function createTestPdf()
      {
        PDF::SetTitle('Hello World');
        PDF::AddPage();
        PDF::Write(0, 'Hello World');
        PDF::Output('hello_world.pdf');
  
        echo "Fatto!";
      }
  }
  </code></pre>
  
  <p>with a basic route:</p>
  
  <pre><code>$app-&gt;get('pdf', 'PdfController@createTestPdf');
  </code></pre>
  
  <p>But when I try to access to <code>/pdf</code> I get the following error:</p>
  
  <pre><code>Fatal error: Class 'PDF' not found in /Users/m/Documents/Projects/lumen-pdf/app/Http/Controllers/PdfController.php on line 15
  
  (1/1) FatalErrorException
  Class 'PDF' not found
  in PdfController.php (line 15)
  at Application-&gt;handleShutdown()
  in RegistersExceptionHandlers.php (line 54)
  at Application-&gt;Laravel\Lumen\Concerns\{closure}()
  </code></pre>
  
  <p>Could you help me please?</p>