Ensure that all non-lazy-init singletons are instantiated, also considering IFactoryObjects.
Typically invoked at the end of factory setup, if desired.
As this is a startup method, it should destroy already created singletons if it fails, to avoid dangling resources. In other words, after invocation of that method, either all or no singletons at all should be instantiated.
|ObjectsException||If one of the singleton objects could not be created.|