<<rule>> Delete: Enumeration Attribute

<<preserve>> fromContainerClass : EClass <<delete>> oldAttribute : EAttribute <<delete>> defaultValueLiteral = literalName <<preserve>> fromEnumeration : EEnum <<require, pre>> preLiteral : EEnumLiteral <<require, pre>> name = literalName <<delete>> eType <<delete>> eContainingClass eStructuralFeatures <<require, pre>> eEnum eLiterals