Added a World.getWorldType() method

By: Nathan Adams <dinnerbone@dinnerbone.com>

paper-api/src/main/java/org/bukkit/World.java

@@ -746,6 +746,13 @@ public interface World extends PluginMessageRecipient {
      */
     public File getWorldFolder();
 
+    /**
+     * Gets the type of this world.
+     *
+     * @return Type of this world.
+     */
+    public WorldType getWorldType();
+
     /**
      * Represents various map environment types that a world may be
      */