fixing type inheritence

The problem:
• create a base type in the graph with an attribute
• declare the same type in code overwrite the attribute with a non-kaiso attribute type
• create a subclass of the type in data
• create an instance of the subclass with a value for the declared attribute
• retrieve the instance from the graph

The attribute on the retrieved instance is not of the correct type and value.
The instance should not be an instance of the code declared base-class.