Introduction
A specialization of MultiGanttChartContainer capable of displaying exactly four instances of GanttChart and keeping their layouts (same table width, same timeline) and their scrolling and zooming behavior in synch. The container distinguishes between the Gantt chart locations UPPER_LEFT, UPPER_RIGHT, LOWER_LEFT, LOWER_RIGHT. The timelines of the UPPER_LEFT and LOWER_LEFT Gantt charts are scrolling in sync and the timelines of the UPPER_RIGHT and LOWER_RIGHT are scrolling in sync.
