This overrides the parent's method in order to allow the parameters to
be provided as a hash reference.
-=item B<< $metaclass->constructor_class ($class_name) >>
+=item B<< $metaclass->constructor_class($class_name) >>
-=item B<< $metaclass->destructor_class ($class_name) >>
+=item B<< $metaclass->destructor_class($class_name) >>
These are the names of classes used when making a class
immutable. These default to L<Moose::Meta::Method::Constructor> and