Chiseled Bookshelf/BE


 * Block entity data
 * : List of books in the bookshelf, in order of addition.
 * : An item, including the slot tag. The valid slot numbers are 0-5. When pushing an item, it will be append to the tail of the list. When pulling an item, the first (by hopper) or the last (by player) item will be pulled from the list.
 * : An item, including the slot tag. The valid slot numbers are 0-5. When pushing an item, it will be append to the tail of the list. When pulling an item, the first (by hopper) or the last (by player) item will be pulled from the list.