Added a display name to Actors

worldedit-core/src/main/java/com/sk89q/worldedit/extension/platform/PlayerProxy.java

@@ -82,6 +82,11 @@ class PlayerProxy extends AbstractPlayerActor {
         return basePlayer.getName();
     }
 
+    @Override
+    public String getDisplayName() {
+        return basePlayer.getDisplayName();
+    }
+
     @Override
     public BaseEntity getState() {
         throw new UnsupportedOperationException("Can't getState() on a player");