refactor main method signature and enhance config initialization

src/de/miaurizius/jgame2d/core/Boot.java

@@ -19,7 +19,7 @@ public class Boot {
         }
     }
 
-    static void main() {
+    public static void main(String[] args) {
         generateWindow();
 
         gamePanel.setupGame();

src/de/miaurizius/jgame2d/core/Config.java

@@ -10,9 +10,11 @@ public class Config {
     private final GamePanel panel;
     private final HashMap<String, String> settings = new HashMap<>();
 
-    public Config(GamePanel panel) {
+    public Config(GamePanel panel) throws IOException {
         this.panel = panel;
         for (Setting option : Setting.values()) settings.put(option.name, null);
+        new File("gamedata").mkdirs();
+        new File("gamedata/config").createNewFile();
     }
 
     // GENERAL

src/de/miaurizius/jgame2d/core/enums/Map.java

@@ -3,7 +3,7 @@ package de.miaurizius.jgame2d.core.enums;
 public enum Map {
 
     OVERWORLD("worldmap", 0),
-    HUT("worldmap", 1);
+    HUT("indoor01", 1);
 
     private final String name;
     private final int index;