Single collection endpoint

[jgonggrijp]

This is an RDF endpoint (#157) where a client can

• [ ] Send a GET request to retrieve information about a single collection.
  • This does not include a listing of records within the collection.
  • This does not include a listing of users that have access to the collection.
• [ ] Send a PUT or PATCH request to change the collection (primarily its name).
• [ ] Send a DELETE request in order to delete the collection.
• [ ] Send POST requests with varying payloads in order to add and remove records to/from the collection.
  • [ ] These operations require a small domain-specific language (DSL) which could be based either on RDF or plain JSON.

The modifying operations (everything except for the GET) must be only possible if the user has sufficient permission to execute them.

Best implemented after #159.