Added a compatibility member function in global event type to comply with the other event types.
Encapsulate constructors in global filters and disable them in script.
Disable the copy constructor in global filters.
Allow inclusion/exclusion member functions return boolean if the specified entity could be filtered or not.
Remove useless checks inside global filters since they cannot be unparented anymore.
Test whether an entity is enabled before hooking, unhooking from it inside global filters.
