new NPC for ToL support

src/engine/gameManager/BuildingManager.java

@@ -520,7 +520,7 @@ public enum BuildingManager {
         if (building.getBlueprintUUID() == 0)
             return false;
 
-        if (building.getBlueprint().getMaxSlots() == building.getHirelings().size())
+        if (building.getBlueprint().getSlotsForRank(building.getRank()) == building.getHirelings().size())
             return false;
 
         String pirateName = NPCManager.getPirateName(contract.getMobbaseID());