Have Picker use controlling instead of root

In order to share property with base class.

Author: vidartf

examples/Examples.ipynb

@@ -107,8 +107,8 @@
     "hover_point = Mesh(geometry=SphereGeometry(radius=0.05),\n",
     "                   material=MeshLambertMaterial(color='hotpink'))\n",
     "\n",
-    "click_picker = Picker(root=surf, event='dblclick')\n",
-    "hover_picker = Picker(root=surf, event='mousemove')\n",
+    "click_picker = Picker(controlling=surf, event='dblclick')\n",
+    "hover_picker = Picker(controlling=surf, event='mousemove')\n",
     "\n",
     "# Set up scene:\n",
     "key_light = DirectionalLight(color='white', position=[3, 5, 1], intensity=0.4)\n",

js/scripts/three-class-config.js

@@ -251,7 +251,6 @@ module.exports = {
         superClass: 'Controls',
         properties: {
             event:          new Types.String('click'),
-            root:           new Types.ThreeType('Object3D', {nullable: true}),
             all:            new Types.Bool(false),
             distance:       new Types.Float(null, {nullable: true}),
             point:          new Types.Vector3(0, 0, 0),

js/src/controls/Picker.js

@@ -35,7 +35,7 @@ var PickerModel = PickerAutogen.PickerModel.extend({
 
     onPick: function() {
         var mouse = this.obj.pickCoordinates;
-        var objects = pick(mouse, this.camera, this.get('root').obj);
+        var objects = pick(mouse, this.camera, this.get('controlling').obj);
 
         var info = getinfo(objects.length > 0 ? objects[0] : null);