examine signature changed to include distance

- distance is INFINITE, 0, or a positive integer based on get_dist() between
the examiner and examinee's turfs when they are on the same Z. When the
examiner is dead or a ghost, distance is always 0.
- also updates /examine( implementations to use it!
- adds w_class_to_name proc for reusing "It is a X item." examine behavior.

code/modules/mining/fulton.dm

@@ -12,7 +12,7 @@ var/global/list/total_extraction_beacons = list()
 	var/can_use_indoors = FALSE
 	var/safe_for_living_creatures = 1
 
-/obj/item/extraction_pack/examine()
+/obj/item/extraction_pack/examine(mob/user, distance, infix, suffix)
 	. = ..()
 	. += "It has [uses_left] use\s remaining."
 

code/modules/mining/ore_box.dm

@@ -13,9 +13,9 @@
 	var/stored_ore
 
 
-/obj/structure/ore_box/examine(mob/user)
+/obj/structure/ore_box/examine(mob/user, distance, infix, suffix)
 	. = ..()
-	if (!Adjacent(user) && !isobserver(user))
+	if (distance > 2 && !isobserver(user))
 		return
 	if (isliving(user))
 		add_fingerprint(user)

code/modules/mining/ore_redemption_machine/mine_point_items.dm

@@ -37,7 +37,7 @@
 
 	..()
 
-/obj/item/card/mining_point_card/examine(mob/user)
+/obj/item/card/mining_point_card/examine(mob/user, distance, infix, suffix)
 	. = ..()
 	. += "There's [mine_points] excavation points on the card."
 	. += "There's [survey_points] survey points on the card."