Implement getNameUnsafe method to allow an unloaded world's name to be accessed (#1712)

* Implement getNameUnsafe method to allow an unloaded world's name to be accessed
 - Fixes #1671 and #504

* Add javadoc since tag

Co-authored-by: Alexander Brandes <mc.cache@web.de>

Co-authored-by: Alexander Brandes <mc.cache@web.de>

worldedit-core/src/main/java/com/sk89q/worldedit/world/NullWorld.java

@@ -69,6 +69,13 @@ public class NullWorld extends AbstractWorld {
         return "null";
     }
 
+    //FAWE start - allow history to read an unloaded world's name
+    @Override
+    public String getNameUnsafe() {
+        return "null";
+    }
+    //FAWE end
+
     @Override
     public String getId() {
         return "null";

worldedit-core/src/main/java/com/sk89q/worldedit/world/World.java

@@ -63,12 +63,23 @@ public interface World extends Extent, Keyed, IChunkCache<IChunkGet> {
 //FAWE end
 
     /**
-     * Get the name of the world.
+     * Get the name of the world. This will error if world has been unloaded by the server.
      *
      * @return a name for the world
      */
     String getName();
 
+    //FAWE start - allow history to read an unloaded world's name
+    /**
+     * Get the name of the world. If the world referenced has been unloaded, this will still return the name.
+     *
+     * @return a name for the world
+     * @since TODO
+     */
+    String getNameUnsafe();
+    //FAWE end
+
+
     /**
      * Get the folder in which this world is stored. May return null if unknown
      * or if this world is not serialized to disk.