Powernet rework

code/controllers/Processes/machinery.dm

@@ -4,6 +4,7 @@
 
 /datum/controller/process/machinery/doWork()
 	process_power()
+	process_power_drain()
 	process_machines()
 
 /datum/controller/process/machinery/proc/process_machines()
@@ -40,5 +41,12 @@
 			powerNetwork.reset()
 			scheck()
 			continue
-		else
-			powernets -= powerNetwork
+			
+		powernets.Remove(powerNetwork)
+		
+/datum/controller/process/machinery/proc/process_power_drain()
+	// Currently only used by powersinks. These items get priority processed before machinery
+	for(var/obj/item/I in processing_power_items)
+		if(!I.pwr_drain()) // 0 = Process Kill, remove from processing list.
+			processing_power_items.Remove(I)
+		scheck()