Label should only be required if it's used in the URI #126
Description
Currently the codelist-pipeline and components-pipeline require that a label be provided. These are only required because they might be used in the URI (forming the default values for notation). If a notation is provided, then the label isn't required (at least not to create the RDF, although it's highly desirable for the UI). Perhaps we could relax the validation but still ensure that everything is present to complete the URI template.
Ultimately we want to ensure the uniqueness of code and component URIs.