Add "changeType" to onChange() function

Hello,

Could you add an extra parameter to the `onChange()` function prop for the `<Spreadsheet>` component that specifies in the manner the data was changed? i.e. if the change was caused by typing, pasting, deleting, etc?

I have some data cleanup that needs to happen when information is pasted into the spreadsheet, but not when values are being typed in by hand.

Thanks!