Add a with_cuts method to FKTableData

Created by: Zaharid

Allow to apply cuts to the new FKtable representation in a way that the index is kept properly matched.

This is going to be useful to get full-fledged predictions out of this object.

It may be useful to have this functionality at the level of the parser when we get a nicer file format (in addition to or instead of here), but for now it is probably fine to have it here.