Show confirmation after note is sent

src/main/java/service/NoteService.java

@@ -43,6 +43,12 @@ public class NoteService {
     }
 
     private boolean send(Note note) {
+        // TODO: handle the following cases (originally listed at PacketCreator#noteError)
+        /*
+         *  0 = Player online, use whisper
+         *  1 = Check player's name
+         *  2 = Receiver inbox full
+         */
         try {
             noteDao.save(note);
             return true;