[dxwg] Clarify abstract list operations can be realized in a single API

azaroth42 has just created a new issue for https://github.com/w3c/dxwg:

== Clarify abstract list operations can be realized in a single API  ==
(conneg)

The two abstract operations for listing could be implemented in a realization using a single call, e.g. 
```
{
  "http://example.org/profile/1": "1",
  "http://example.org/profile/2"; "2"
}
```
As a response includes the list of URIs _and_ the short token to use for it.
If this is an acceptable realization, this should be clarified in section 5.



Please view or discuss this issue at https://github.com/w3c/dxwg/issues/548 using your GitHub account