update to allow book to be sold

sorry that I do not provide a way to remove book [read], because this mod is just aim at preserve information.

--What this mod does: After you have translated and studied a book, it generate a card with no aspects. This card serves as a little text reminder containing info that you can see through studying the book.
--Problem: I only test this mod once and in hurry, I don't know how to eliminate the generated cards, that sounds quite disconcerting.

My guess concerning the mod is that it keeps the book from being consumed by the act of reading said material and simply flagged as 'learned', making re-reading either less useful or letting you be able to simply sell the book to get rid of it.

what