Exp gain & Chaos scroll fix + Diet's MK Overhaul

Fixed issues with negative experience being distributed to characters
when killing a mob, rendering "Exp reset". Fixed chaos scroll behaving
oddly. Refactored debuff expirations to manage one list with registered
debuffs and expire times, thus lifting some load from the TimerManager.
Added concurrency protection on how World deals with parties. Thanks to
the DietStory dev team, fixed some issues with the MK maps.

scripts/npc/1300013.js

@@ -0,0 +1,40 @@
+/*
+	NPC: Blocked Entrance (portal?)
+	MAP: Mushroom Castle - East Castle Tower (106021400)
+*/
+
+var status;
+
+function start(){
+	status = -1;
+	action(1, 0, 0);
+}
+
+function action(mode, type, selection){
+	if(mode == -1){
+		cm.dispose();
+		return;
+	}
+	else if(mode == 0 && status == 0){
+		cm.dispose();
+		return;
+	}
+	else if(mode == 0)
+		status--;
+	else
+		status++;
+
+
+	if(status == 0){
+		cm.sendSimple("#L1#Enter to fight #bKing Pepe#k and #bYeti Brothers#k.#l");
+	}
+	else if(status == 1){
+		if(selection == 1){
+			var pepe = cm.getEventManager("KingPepeAndYetis");
+			pepe.setProperty("player", cm.getPlayer().getName());
+			pepe.startInstance(cm.getPlayer());
+			cm.dispose();
+			return;
+		}
+	}
+}