UMLR — Classifier.allSlottableFeatures shall incorporate redefinition

The Operation Classifier.allSlottableFeatures() is not correct for it does not take into account potentially redefined StructuralFeatures. This leads to a situation where Feature are defined as slottable that are, in fact, not visible in the scope of the Classifier of an InstanceSpecification.

There are two options:
1. Enhance allSlottableFeatures in a way that redefined StructuralFeatures are resolved first.
2. Introduce another operation allEffectiveSlottableFeatures that invokes allSlottableFeatures and resolves the redefinition of those Features afterwards.

In my opinion, option 1 should be followed.