Wrong value for IsAbstract for most UA ReferenceTypes

[JimLuth]

The IsAbstract attribute is inherited from the base AML Interface class "Refererences" where it is set to True, but it seems it is never overridden and set to True as it should be for most of the derived interface classes. For instance the Organizes interface class should have IsAbstract set to False. See attached screen shot.

[Archie-Miller]

The editor is picking this up, from where, I do not know (probably it's parent - HierachicalReferences).

The actual xml does not have the IsAbstract Attribute. A false value to IsAbstract is ignored in AddModifyAttribute.