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/blob2/blobs/base_blob.dm

@@ -69,7 +69,7 @@ GLOBAL_LIST_EMPTY(all_blobs)
 			return TRUE
 	return FALSE
 
-/obj/structure/blob/examine(mob/user)
+/obj/structure/blob/examine(mob/user, distance, infix, suffix)
 	. = ..()
 	if(!overmind)
 		. += "It seems inert." // Dead blob.