This sample visualizes an organizational structure along with an overview for easily navigating the large organizational structure using Overview control.
                        This example shows how to render the overview control and how to
                        display a preview (overall view) of the entire content of a diagram.
                        This helps you look at the overall picture of a large diagram and
                        also to navigate (pan or zoom) to a particular position of the page.
                        The sourceID property can be used to map the diagram
                        control with overview.