Add EMPTY_MAP and STICK item material constants

Signed-off-by: Irmo van den Berge <irmo.vandenberge@ziggo.nl>

src/main/java/com/bergerkiller/bukkit/common/inventory/CommonItemMaterials.java

@@ -12,4 +12,6 @@ public class CommonItemMaterials {
     public static final Material SKULL = MaterialUtil.getFirst("PLAYER_HEAD", "LEGACY_SKULL_ITEM");
     public static final Material FILLED_MAP = CommonCapabilities.MATERIAL_ENUM_CHANGES ?
             CommonLegacyMaterials.getMaterial("FILLED_MAP") : CommonLegacyMaterials.getLegacyMaterial("MAP");
+    public static final Material EMPTY_MAP = MaterialUtil.getFirst("MAP", "LEGACY_EMPTY_MAP");
+    public static final Material STICK = MaterialUtil.getFirst("STICK", "LEGACY_STICK");
 }