Groups now update their children across preUpdate, update and postUpdate.

Sprite.exists = false removes Body from world.

src/core/Group.js

@@ -33,7 +33,7 @@ Phaser.Group = function (game, parent, name, addToStage) {
 
     PIXI.DisplayObjectContainer.call(this);
 
-    if (typeof addToStage === 'undefined')
+    if (typeof addToStage === 'undefined' || addToStage === false)
     {
         if (parent)
         {
@@ -70,7 +70,6 @@ Phaser.Group = function (game, parent, name, addToStage) {
     /**
     * @property {Phaser.Group|Phaser.Sprite} parent - The parent of this Group.
     */
-    // this.group = null;
 
     /**
     * @property {Phaser.Point} scale - The scale of the Group container.
@@ -125,8 +124,6 @@ Phaser.Group.SORT_ASCENDING = -1;
 */
 Phaser.Group.SORT_DESCENDING = 1;
 
-// PIXI.DisplayObjectContainer.prototype.addChildAt = function(child, index)
-
 /**
 * Adds an existing object to this Group. The object can be an instance of Phaser.Sprite, Phaser.Button or any other display object.
 * The child is automatically added to the top of the Group, so renders on-top of everything else within the Group. If you need to control
@@ -704,6 +701,57 @@ Phaser.Group.prototype.callAll = function (method, context) {
 
 }
 
+/**
+* The core preUpdate - as called by World.
+* @method Phaser.Group#preUpdate
+* @protected
+*/
+Phaser.Group.prototype.preUpdate = function () {
+
+    for (var i = 0, len = this.children.length; i < len; i++)
+    {
+        if (this.children[i]['preUpdate'])
+        {
+            this.children[i].preUpdate();
+        }
+    }
+
+}
+
+/**
+* The core update - as called by World.
+* @method Phaser.Group#update
+* @protected
+*/
+Phaser.Group.prototype.update = function () {
+
+    for (var i = 0, len = this.children.length; i < len; i++)
+    {
+        if (this.children[i]['update'])
+        {
+            this.children[i].update();
+        }
+    }
+
+}
+
+/**
+* The core postUpdate - as called by World.
+* @method Phaser.Group#postUpdate
+* @protected
+*/
+Phaser.Group.prototype.postUpdate = function () {
+
+    for (var i = 0, len = this.children.length; i < len; i++)
+    {
+        if (this.children[i]['postUpdate'])
+        {
+            this.children[i].postUpdate();
+        }
+    }
+
+}
+
 /**
 * Allows you to call your own function on each member of this Group. You must pass the callback and context in which it will run.
 * After the checkExists parameter you can add as many parameters as you like, which will all be passed to the callback along with the child.