switch to uncharted2 tone mapping by default in example.

examples/webgl_tonemapping.html

@@ -65,7 +65,7 @@
 				bumpScale: 0.3,
 				exposure: 1.0,
 				whitePoint: 1.0,
-				toneMapping: "Reinhard"
+				toneMapping: "Uncharted2"
 			};
 
 			var toneMappingOptions = {