de.digitalcollections.model dc-model-xml 8.2.1 8.2.1 2.2.0 3.0.0 4.0.0 4.0.1 4.0.2 6.1.0 6.1.1 6.2.0 6.2.1 7.0.0 8.0.0 8.1.0 8.2.0 8.2.1 20210224095532