add BatMON and SkeletonLordMON; update AssetSetter to include new monsters and adjust player interaction

src/de/miaurizius/jgame2d/data/DataStorage.java

@@ -1,5 +1,7 @@
 package de.miaurizius.jgame2d.data;
 
+import de.miaurizius.jgame2d.core.enums.Map;
+
 import java.io.Serializable;
 import java.util.ArrayList;
 import java.util.List;
@@ -19,6 +21,7 @@ public class DataStorage implements Serializable {
     int nextLevelExp;
     int coins;
     int worldX, worldY;
+    Map currentMap;
 
     // PLAYER INVENTORY
     List<String> itemNames = new ArrayList<>();