Merge pull request #4097 from deathride58/theprthatbulliesjanitormains

[READY] Makes walking on tiles slowly make them dirty, similar to Baystation, and adds footstep sounds (Featuring sounds from CEV Eris!)

code/citadel/crew_objectives/cit_crewobjectives_civilian.dm

@@ -107,7 +107,8 @@
 /datum/objective/crew/clean/check_completion()
 	for(var/area/A in areas)
 		for(var/obj/effect/decal/cleanable/C in area_contents(A))
-			return FALSE
+			if(C && C.alpha >= 150)
+				return FALSE
 	return TRUE
 
 /datum/objective/crew/slipster //ported from old Hippie with adjustments

code/modules/mob/living/simple_animal/bot/cleanbot.dm

@@ -181,7 +181,7 @@
 		/obj/effect/decal/cleanable/flour,
 		/obj/effect/decal/cleanable/ash,
 		/obj/effect/decal/cleanable/greenglow,
-		/obj/effect/decal/cleanable/dirt,
+		///obj/effect/decal/cleanable/dirt, Cit change - removes dirt from the cleanbot target list to compensate for the mass amount of dirt decals present with footdirt
 		/obj/effect/decal/cleanable/deadcockroach,
 		/obj/effect/decal/remains
 		)