message: Added navigation to barcode scan page.
diff: <li><a href="examples/qr-image">Scan QR Code from Image</a></li>
  <li><a href="examples/qr-video">Scan QR Code from Video File</a></li>
  <li><a href="examples/qr-svg-writer">Write QR Code to SVG</a></li>
  + <li><a href="examples/barcode-camera">Scan Barcode from Video Camera</a></li>
  </ul>
  <p>
  