title: symfony2 and dropzone.js save issues
body: <p>I've one application to upload files.
  I'm using the script Dropzone.js and i followed one answer here to make this working with symfony.</p>
  
  <p>the controller:</p>
  
  <pre><code>    public function indexAction() {
          return $this-&gt;render('testDropzoneBundle:Default:index.html.twig');
      }
  
      public function uploadAction() {
          $request = $this-&gt;get('request');
          $files = $request-&gt;files;
  
          foreach ($files as $uploadedFile) {
              $name = uniqid();
              $em = $this-&gt;getDoctrine()-&gt;getManager();
              $f = new File();
              $f-&gt;setName(($uploadedFile-&gt;getClientOriginalName());
              $f-&gt;setFile($uploadedFile);
              $f-&gt;preUpload();
              $f-&gt;upload();
              $em-&gt;persist($f);
              $em-&gt;flush();
          }
          return new Response($name);
      }
  </code></pre>
  
  <p>and the view:</p>
  
  <pre><code>&lt;form action="{{ path('upload') }}" method="post" class="dropzone"&gt;
  &lt;div class="fallback" id="mydropzone"&gt;
      &lt;input name="file" type="file" multiple /&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p></p>
  
  <p>but now I want to set a name for each file that I drag on the page.
  I want to show a dialog asking the name.
  like this:
  dropzone.js line 538</p>
  
  <pre><code>var myName = prompt('Enter the name for file '+file.name);
  file.name = myName;
  </code></pre>
  
  <p>But how can I send the name from the script to controller?</p>