Don't fail to load plugin if "Floor" is missing in elevator movement,…

… this happens because emergency stop was thrown. Floor is null

src/main/java/com/andrew121410/mc/world16elevators/storage/serializers/ElevatorMovementSerializer.java

@@ -18,7 +18,7 @@ public ElevatorMovement deserialize(Type type, ConfigurationNode node) throws Se
             return null;
         }
 
-        Integer floor = SerializerUtils.nonVirtualNode(node, "Floor").getInt();
+        Integer floor = node.node("Floor").get(Integer.class);
         Location location = SerializerUtils.nonVirtualNode(node, "AtDoor").get(Location.class);
         BoundingBox boundingBox = SerializerUtils.nonVirtualNode(node, "BoundingBox").get(BoundingBox.class);