Feature #17944

Updated by Ward Vandewege 10 months ago

Cf. https://doc.arvados.org/admin/workbench2-vocabulary.html

* get the vocabulary file from the Workbench/VocabularyURL config value
* apply validation before save/update requests. Admin users do not get special treatment.

* the validation code should handle existing data gracefully: if tags are not being changed but are invalid, updates to other fields in the collection should still be permitted.
* migrate the configuration config parameter to Collections/VocabularyURL. Continue to accept the old config location and log a warning.