Refactor move/click code

code/modules/mob/living/simple_mob/simple_mob.dm

@@ -194,7 +194,7 @@
 	. = ..()
 	to_chat(src,"<b>You are \the [src].</b> [player_msg]")
 
-/mob/living/simple_mob/SelfMove(turf/n, direct)
+/mob/living/simple_mob/SelfMove(turf/n, direct, movetime)
 	var/turf/old_turf = get_turf(src)
 	var/old_dir = dir
 	. = ..()
@@ -212,9 +212,9 @@
 	return ..()
 */
 /mob/living/simple_mob/movement_delay()
-	var/tally = 0 //Incase I need to add stuff other than "speed" later
+	. = ..()
 
-	tally = movement_cooldown
+	. += movement_cooldown
 
 	if(force_max_speed)
 		return -3
@@ -223,25 +223,25 @@
 		if(!isnull(M.haste) && M.haste == TRUE)
 			return -3
 		if(!isnull(M.slowdown))
-			tally += M.slowdown
+			. += M.slowdown
 
 	// Turf related slowdown
 	var/turf/T = get_turf(src)
 	if(T && T.movement_cost && !hovering) // Flying mobs ignore turf-based slowdown. Aquatic mobs ignore water slowdown, and can gain bonus speed in it.
 		if(istype(T,/turf/simulated/floor/water) && aquatic_movement)
-			tally -= aquatic_movement - 1
+			. -= aquatic_movement - 1
 		else
-			tally += T.movement_cost
+			. += T.movement_cost
 
 	if(purge)//Purged creatures will move more slowly. The more time before their purge stops, the slower they'll move.
-		if(tally <= 0)
-			tally = 1
-		tally *= purge
+		if(. <= 0)
+			. = 1
+		. *= purge
 
 	if(m_intent == "walk")
-		tally *= 1.5
+		. *= 1.5
 
-	return tally+config.animal_delay
+	 . += config.animal_delay
 
 
 /mob/living/simple_mob/Stat()