Row Spanning
Row spanning is done by add a rowSpan?: (item: T) => number function to a column definition. Anything greater than 1 will make the cell span into adjacent cells. -1 means span over all rows in the grid area.
Row spanning is done by add a rowSpan?: (item: T) => number function to a column definition. Anything greater than 1 will make the cell span into adjacent cells. -1 means span over all rows in the grid area.