Move (most) hardcoded defaults to MazeDefault

- harcoded values centralized
- IntegerField for JTextField containing numbers
- fix, can draw even if topleft position is not (0,0) ( ie if scrollbar were used )

java/org/artisanlogiciel/games/maze/gui/component/Panel.java

@@ -0,0 +1,14 @@
+package org.artisanlogiciel.games.maze.gui.component;
+
+import javax.swing.*;
+
+public class Panel
+extends JPanel {
+
+    protected void addField(IntegerField pField)
+    {
+        add(pField.getLabel());
+        add(pField.getTextField());
+    }
+
+}