title: FabricJS: fabric.Image.filters.RemoveColor is not a constructor
body: <p>I am trying to use filters for an image, specifically the RemoveColor filter. </p>
  
  <p>I have this working for Invert...</p>
  
  <pre><code>var object = canvas.getActiveObject();
  var filter = new fabric.Image.filters.Invert();
  object.filters.push(filter);
  object.applyFilters(canvas.renderAll.bind(canvas));
  </code></pre>
  
  <p>But using this code for RemoveColor...</p>
  
  <pre><code>var object = canvas.getActiveObject();
  var filter = new fabric.Image.filters.RemoveColor({
    color: color.rgb,
    threshold: this.props.currentRemoveColorDistance,
  });
  object.filters.push(filter);
  object.applyFilters();
  canvas.renderAll();
  </code></pre>
  
  <p>returns this error...</p>
  
  <blockquote>
    <p>Uncaught TypeError: fabric.Image.filters.RemoveColor is not a
    constructor</p>
  </blockquote>
  
  <p>If I <code>console.log(fabric.Image.filters)</code>, I can see that the RemoveColor property is indeed missing, but there is a RemoveWhite instead...</p>
  
  <pre><code>BaseFilter
  Blend
  Brightness
  ColorMatrix
  Contrast
  Convolute
  GradientTransparency
  Grayscale
  Invert
  Mask
  Multiply
  Noise
  Pixelate
  RemoveWhite
  Resize
  Saturate
  Sepia
  Sepia2
  Tint
  </code></pre>
  
  <p>After trying RemoveWhite, it works but of course, only the white is removed which is not what I want. </p>
  
  <p>Where is RemoveColor?</p>
  
  <p>I am using npm "fabric": "^1.7.22"</p>