UMLR — Rename Specialization/Generalization between abstract classes

Inheritance between an abstract and a solid class should not be named Inheritance (or specialization or generalization).
Reason: If abstract classes do not have filled in methods, the concrete class just implements them, not extend. Therefore inheritance between concrete class and an abstract class is really an implementation. But implementation is used for interfaces. Therefore we need different name to describe the relationship between abstract class and concrete class.