title: How to turn the camera light (torch) off?
body: <p>I'm creating an app to read barcodes. I'm using QuaggaJS as a barcode reader library. My problem is that I can turn the torch on, but I can't turn it off.</p>
  
  <pre><code>var track = Quagga.CameraAccess.getActiveTrack();
  track.applyConstraints({advanced: [{torch:true}]}); //Torch is on
  track.applyConstraints({advanced: [{torch:false}]}); //Torch still on :(
  </code></pre>
  
  <p>Is there a way to turn the torch off?</p>