title: DropZone acceptedFiles type filter
body: <p>I've got a <a href="https://github.com/enyo/dropzone">DropZone</a> form working perfectly with one exception, I can't seem to limit the file types as precisely as I need to. </p>
  
  <p>Using <code>acceptedFiles: "image/*"</code> dims all folders and file types that are not images, as it should. <em>TIFF</em> is included though and I need to reduce it to exclusively <em>JPG</em> and <em>PNG</em>. A lot of trial and error has not gotten me there.</p>
  
  <p>What I tried:</p>
  
  <pre><code>acceptedFiles: "image/jpg"
  acceptedFiles: ".jpeg,.jpg,.png"
  acceptedFiles: "image/jpg,png"
  </code></pre>
  
  <p>But they all make everything selectable.</p>
  
  <p>What's the correct format for just <em>JPG</em> and <em>PNG</em>?</p>