ui.table respond to format prop changes

[mattrunyon]

ui.table currently does not respond to the format_ prop changing. It takes the initial value and leaves it at that.

We should probably use fast-deep-equal and make a hook to keep the value based on deep equality. That way we can respond to user changes to the format without reloading the table on every prop change.

We could create a map of if_ value to column names so we can only add/remove custom columns as necessary if any change instead of reloading the whole table on any format change.