Feature request: cell selection, hover text

[wyu]

Thanks for the great work! The plot looks great and easy to use from a data frame.

I'm wonder if there is a way to capture the cell selection when the user click on a cell, so we can implement drill-down or other interaction.

The labels can also be too longer for a cell, so it makes more sense to divide the description into ID and hints, which is not displayed until the mouse over event is triggered.

Thanks!
Wen