Describe runid clearer in API documentation

Issue #111 resolved
Peter Dekker
created an issue

The participant guide tells participants that the runid, supplied when submitting a run, is used purely for your own bookkeeping:

However, the API documentation does not make this clear: It is even confusing, by saying "Note that the runid is used to identify queries within a specific run."

The API documentation of the runid field should be made clearer