Fix ErrorLogger

src/de/steamwar/bungeecore/ErrorLogger.java

@@ -89,6 +89,7 @@ public class ErrorLogger extends Handler {
         contains.add("Connection reset by peer");
         contains.add("No client connected for pending server");
         contains.add("Error occurred processing connection for");
+        contains.add("Server is online mode!");
         ignoreContains = Collections.unmodifiableList(contains);
     }
 }