Add better Fail massage than standard bungee

Signed-off-by: Lixfel <agga-games@gmx.de>

src/de/steamwar/bungeecore/listeners/TablistManager.java

@@ -18,6 +18,7 @@ import java.io.File;
 import java.io.IOException;
 import java.util.*;
 import java.util.concurrent.TimeUnit;
+import java.util.logging.Level;
 
 public class TablistManager extends BasicListener {
 
@@ -78,6 +79,7 @@ public class TablistManager extends BasicListener {
     }
 
     private synchronized void updateCustomTablist(){
+        try{
             calcHeader();
 
             //Calculate server-player-map
@@ -109,6 +111,9 @@ public class TablistManager extends BasicListener {
                 tablist.refresh();
 
             seconds++;
+        }catch(NullPointerException e){
+            ProxyServer.getInstance().getLogger().log(Level.SEVERE, "NPE", e);
+        }
     }
 
     @EventHandler