Attempt to enable COOP and COEP so the multithreaded examples work on github.io

Author: jrouwe

Examples/conveyor_belt_threaded.html

@@ -12,6 +12,7 @@
 			This demo shows how to use the contact listener to modify object angular and linear velocity
 		</div>
 
+		<script src="js/coi-serviceworker.min.js"></script>
 		<script src="js/three/three.min.js"></script>
 		<script src="js/three/OrbitControls.js"></script>
 		<script src="js/three/WebGL.js"></script>

Examples/js/coi-serviceworker.min.js

@@ -10,6 +10,7 @@
 		<div id="container">Loading...</div>
 		<div id="info">JoltPhysics.js multi threaded stress test demo</div>
 
+		<script src="js/coi-serviceworker.min.js"></script>
 		<script src="js/three/three.min.js"></script>
 		<script src="js/three/OrbitControls.js"></script>
 		<script src="js/three/WebGL.js"></script>