Fix launch exceptions

SpigotCore_Main/src/de/steamwar/sql/SWException.java

@@ -101,7 +101,13 @@ public class SWException {
         for(Player player : Bukkit.getOnlinePlayers())
             message += player.getName() + " ";
 
+        String server;
+        if(Bukkit.getWorlds().isEmpty())
+            server = Bukkit.getName();
+        else
+            server = Bukkit.getWorlds().get(0).getName();
+
         SQL.update("INSERT INTO Exception (server, message, stacktrace) VALUES (?, ?, ?)",
-                Bukkit.getWorlds().get(0).getName(), message, st);
+                server, message, st);
     }
 }