Reacting to asteroid chunks being created

[thesixthroc]

It seems there is no way in the engine to react to asteroid chunks being created, as they are not entities. The purpose of this request is to be able to suppress the chunk drops of asteroids at runtime, that way I can spawn special asteroids that follow the same gun targeting rules but don't drop chunks.

created_effect is not available and on_trigger_created_entity can never be fired. Supporting the former may be the best option given that dying_trigger_effect has already been ported from entities to asteroid chunks.