enable retina and normalize renderer canvas

index.html

@@ -52,7 +52,7 @@
       var world;
       window.onload = function () {
         console.log("is Retina supported: " + isRetinaSupported());
-        disableRetinaSupport();
+        // disableRetinaSupport();
         world = new WorldMorph(document.getElementById('world'));
         world.worldCanvas.focus();
         new IDE_Morph().openIn(world);

stitchcode/objects.js

@@ -2548,7 +2548,7 @@ StageMorph.prototype.initRenderer = function () {
           this.renderer = new THREE.WebGLRenderer({
               antialias: true,
               alpha: true,
-              canvas: this.penTrails()
+              canvas: normalizeCanvas(this.penTrails())
           });
           console.log("webgl enabled");
           this.renderer_status_msg = "webgl enabled";