Timeline Demo

This demo shows how to add a timeline component to the graph.

Consists of a main graph component that displays the graph and a timeline component that displays the timeline.
Hover/select bars of the timeline to highlight corresponding nodes in the main graph.
The height of the bars in the timeline is determined by the number of node creation/removal events at each time point.
The timeline component in this demo does not include a timeframe rectangle or a play button, but they are by default included in the Timeline class. Make use of them by initializing a default Timeline instance and register event listeners for filter change.

The input data structure can be arbitrary, but it needs to contain information about the start and end time for each node.