WIP minetest <-> laby import/export

- currently possible to export a laby into minetest
- start of a lua content parser to import .we into lab

java/org/artisanlogiciel/games/minetest/Node.java

@@ -4,15 +4,22 @@ public class Node {
     int x;
     int y;
     int z;
-    String material;
+    Material material;
 
-    public Node(int x, int y, int z, String material) {
+    public Node(int x, int y, int z, Material material) {
         this.x = x;
         this.y = y;
         this.z = z;
         this.material = material;
     }
 
+    public Node(int x, int y, int z) {
+        this.x = x;
+        this.y = y;
+        this.z = z;
+        this.material = Material.DEFAULT;
+    }
+
     public int getX() {
         return x;
     }
@@ -25,7 +32,7 @@ public class Node {
         return z;
     }
 
-    public String getMaterial() {
+    public Material getMaterial() {
         return material;
     }
 }