new NPC for ToL support

src/engine/net/client/handlers/ActivateNPCMsgHandler.java

@@ -93,7 +93,7 @@ public class ActivateNPCMsgHandler extends AbstractClientMsgHandler {
                 return false;
             }
 
-            if (building.getBlueprint().getMaxSlots() == building.getHirelings().size())
+            if (building.getBlueprint().getSlotsForRank(building.getRank()) == building.getHirelings().size())
                 return false;
 
             Item contractItem = Item.getFromCache(msg.getContractItem());