Update Message stuff

src/de/steamwar/bungeecore/Message.java

@@ -90,7 +90,7 @@ public class Message {
         if (current.get() != null) current.get().setParent(now);
         if (now != null) {
             current.set(now);
-            bundles.put(bundleKey, now);
+            bundles.putIfAbsent(bundleKey, now);
         }
     }