sort(recursive) {
		// do nothing if there is already a pending sort
		if (!this.pendingSort) {
			if (recursive === true) {
				this.forEach((child) => {
					if (child instanceof Container) {
						// note : this will generate one defered sorting function
						// for each existing containe
						child.sort(recursive);
					}
				});
			}
			this.pendingSort = defer(function () {
				// sort everything in this container
				this.getChildren().sort(this["_sort" + this.sortOn.toUpperCase()]);
				// clear the defer id
				this.pendingSort = null;
				// make sure we redraw everything
				this.isDirty = true;
			}, this);
		}
	}
Manually trigger the sort of all the childs in the container
@param {boolean} [recursive=false] - recursively sort all containers if true