title: How to use Matc tool from google filament
body: <p>I was reading through the filament documentation and they give the comamnd to out .mat files from the jsonish material definition like this :</p>
  <pre><code>matc --reflect parameters filament/src/materials/skybox.mat 
  </code></pre>
  <p>I have two questions, how do I install this matc tool and after making the .mat file, how do I reference it to make the renderablemesh use it?</p>