removes a bunch of unneeded spawns

spawns have a high overhead.

I only went for easy targets, almost every spawn could be removed with a few subsystems in place to handle delays or cooldowns

code/modules/assembly/doorcontrol.dm

@@ -76,7 +76,6 @@
 		if (M.id == src.id)
 			spawn( 0 )
 				M.open()
-				return
 
 	sleep(10)
 
@@ -90,7 +89,6 @@
 		if (M.id == src.id)
 			spawn( 0 )
 				M.close()
-				return
 
 	sleep(10)
 	cooldown = 0

code/modules/assembly/proximity.dm

@@ -56,7 +56,6 @@
 	cooldown = 2
 	spawn(10)
 		process_cooldown()
-	return
 
 
 /obj/item/device/assembly/prox_sensor/process()
@@ -71,15 +70,13 @@
 /obj/item/device/assembly/prox_sensor/dropped()
 	spawn(0)
 		sense()
-		return
-	return
 
 
 /obj/item/device/assembly/prox_sensor/toggle_scan()
 	if(!secured)	return 0
 	scanning = !scanning
 	update_icon()
-	return
+
 
 
 /obj/item/device/assembly/prox_sensor/update_icon()

code/modules/assembly/signaler.dm

@@ -17,7 +17,7 @@
 	..()
 	spawn(40)
 		set_frequency(frequency)
-	return
+
 
 /obj/item/device/assembly/signaler/Destroy()
 	if(SSradio)