title: What shaders are in the three.js ShaderLib?
body: <p>I see in various demos that you can use a shader like so:</p>
  
  <pre><code>shader = THREE.ShaderLib[ "normalmap" ];
  </code></pre>
  
  <p>What other shaders are in ShaderLib, and where is ShaderLib documented? It doesn't even seem to show up in the github repo.</p>