Adds pick-up, drop and throw sounds for items. (#240)

code/modules/library/lib_items.dm

@@ -214,6 +214,8 @@
 	w_class = WEIGHT_CLASS_NORMAL	 //upped to three because books are, y'know, pretty big. (and you could hide them inside eachother recursively forever)
 	attack_verb = list("bashed", "whacked", "educated")
 	resistance_flags = FLAMMABLE
+	drop_sound = 'sound/items/handling/book_drop.ogg'
+	pickup_sound = 'sound/items/handling/book_pickup.ogg'
 	var/dat				//Actual page content
 	var/due_date = 0	//Game time in 1/10th seconds
 	var/author			//Who wrote the thing, can be changed by pen or PC. It is not automatically assigned