Update tracer

BauSystem_Main/src/de/steamwar/bausystem/features/tracer/Trace.java

@@ -137,6 +137,7 @@ public class Trace { // TODO: Add UUID for file saving and so on!
             entityServer.getEntities().forEach(REntity::die);
         } else {
             entityServer = new REntityServer();
+            entityServer.addPlayer(player);
             entityServerMap.put(player, entityServer);
         }
         render(getRecords(), entityServer, playerTraceShowData);
@@ -244,7 +245,9 @@ public class Trace { // TODO: Add UUID for file saving and so on!
      */
     public void hide(Player player) {
         REntityServer entityServer = entityServerMap.remove(player);
-        if (entityServer != null) entityServer.close();
+        if (entityServer == null) return;
+        entityServer.removePlayer(player);
+        if (entityServer.getPlayers().isEmpty()) entityServer.close();
     }
 
     @Override