Add support for documenting Views.

content_model_documentation.routing.yml

src/CMDocumentConnectorTrait.php

src/CMDocumentManager.php

src/CmDocumentViewBuilder.php

src/DocumentableEntityProvider.php

src/Entity/CMDocument.php

src/Form/CMDocumentForm.php

src/Form/ContentModelDocumentationConfigForm.php

src/Plugin/Derivative/DocumentLocalTab.php