code: public Widget put(IWidgetFactory factory, int x, int y) throws IndexOutOfBoundsException {
  		Widget widget = factory.getWidget();
  		put(widget, x, y);
  		return widget;
  	}
docs: Creates new widget and puts it to container
  
  @param factory Factory of new widget
  @param x       Column
  @param y       Row
  @return Instance of created widget
  @throws IndexOutOfBoundsException when specified coordinates are out of range