first .osm format import

- import osm convert it to Drawing and use it as resolved path.
- Not ready , first test over lab/valbonne_oct_2020.osm

java/org/artisanlogiciel/games/maze/LabyModel.java

@@ -557,7 +557,7 @@ public class LabyModel implements WallsProvider {
 
     /**
      * One step in Maze generation process
-     * get last element in open list and explore one random direction with it.
+     * get last element in open list and explore one random free direction with it.
      *
      * @returns whether process closed current node.
      **/
@@ -601,6 +601,7 @@ public class LabyModel implements WallsProvider {
                     }
 
                     if ((newx >= 0) && (newy >= 0) && (newx < width) && (newy < height)) {
+                        // CLEAR is 0 : no tag at all.
                         if ((t[newx][newy]) == CLEAR) {
                             freeDirection.add(Short.valueOf(direction));
                         }
@@ -610,6 +611,7 @@ public class LabyModel implements WallsProvider {
                 if (!freeDirection.isEmpty()) {
                     // control random using our own pseudorandom
                     short direction = 0;
+                    // System.out.println("" + freeDirection.size() + "\n" );
                     if (freeDirection.size() > 1) {
                         direction = freeDirection.get(random.nextInt(freeDirection.size()));
                     } else {