Refactored Zone to new system

src/engine/objects/Zone.java

@@ -213,7 +213,7 @@ public class Zone extends AbstractWorldObject {
 
     public void setParent() {
 
-        this.parent = ZoneManager.getZoneByZoneID(parentZoneID);
+        this.parent = ZoneManager.getZoneByUUID(parentZoneID);
 
         // Seafloor