Usage of IUserContext.getWorkspaceId()

[t-gauss]

The usage of the method above should be checked. It causes issues e.g. with bulk operations. If a model has references in a different namespace a bulk operation (e.g. release) could fail (workspaceId references the workspace of the model - not the reference). For the bulk operations it could be replaced by ModelRepositoryFactory.getRepositoryByNamespace(). Question is if this method makes sense at all - since a user context might not be associated with one namespace.