update toc

threejs/lessons/toc.html

@@ -2,8 +2,11 @@
   <li>Fundamentals</li>
   <ul>
     <li><a href="/threejs/lessons/threejs-fundamentals.html">Three.js Fundamentals</a></li>
+    <li><a href="/threejs/lessons/threejs-responsive.html">Three.js Responsive Design</a></li>
   </ul>
 </ul>
 <ul>
   <li><a href="https://github.com/greggman/threejsfundamentals">github</a></li>
+  <li><a href="https://three.js">three.js</a></li>
+  <li><a href="https://threejs.org/docs/">three.js docs</a></li>
 </ul>