Add java.util.random seed as initial parameter

- prepare for short save allowing to fully recreate initial lab
having only seed and x,y,depth paramters

java/org/artisanlogiciel/games/MazeParams.java

@@ -7,6 +7,9 @@ import java.io.File;
  **/
 public interface MazeParams
 {
+    /** currently seed of java.util.random **/
+    public long getSeed();
+
     public int getWidth();
 
     public int getHeight();