Add script or wrapper to manage vocabularies (or all imported data?) in jskos-server instances

[stefandesu]

In our old cocoda-services repo, we had a import-vocabularies.sh script that uses a vocabularies.txt file to manage imported vocabularies and concepts. It would make sense to extend this to other data types as well, in particular imported concordances and their mappings.

To-Dos:

• Implement equivalent of old import-vocabularies script (done via data import with no target)
• Add filtering (ideally with two separate parameters, one for the instance/target (first "column" in vocabularies.txt), one for scheme URI)
• Potentially adjust how jskos-data repository is included here (problem: making sure all dependencies for all vocabularies are working correctly is annoying; it might be easier to move that to a Docker image as well where dependencies are easier to track)
• Fix issue with reset requiring confirmation for every single entry (low priority)
• Support .env files for determining baseUrl (low priority)