EDIT

minor

Allowed replace(T x, T y) to accept null for the second argument and globally replace x with null or remove x from collections

Altered ReferringObjectMetadataFactoryImpl to exclude bidirectional relationships where the replaced entity is the "owner" of the related entity (i.e. the relationship is mapped by @OneToMany & mappedBy != null) since those kind of relationships don't make sense in the context of a global replace method.

ReferringObjectMetadata now queries higher up the hierarchy of classes to obtain a reference to a property

Added public T replace(T x, T y) to ICdmEntityDao, implementation and tests