reduced lag, when killing bots all together

a little housekeeping

source/interface.cpp

@@ -2055,6 +2055,9 @@ void ServerActivate (edict_t *pentEdictList, int edictCount, int clientMax)
    waypoints.Init ();
    waypoints.Load ();
 
+   // create global killer entity
+   bots.CreateKillerEntity ();
+
    // execute main config
    ServerCommand ("exec addons/yapb/conf/yapb.cfg");
 
@@ -2089,6 +2092,9 @@ void ServerDeactivate (void)
    waypoints.SaveExperienceTab ();
    waypoints.SaveVisibilityTab ();
 
+   // destroy global killer entity
+   bots.DestroyKillerEntity ();
+
    FreeLibraryMemory ();
 
    if (g_isMetamod)