cohortDiagnostics in plp skeleton?

[ChungsooKim]

How about adding the cohortDiagnostics function in patient level prediction skeleton?
The cohortDiagnostic function is useful, but I always implant it manually.
I already have experience with that, so I can share and put the PR.

[jreps]

I agree :). We are thinking about ways to combine the different study type jsons (e.g., cohortDiagnostic json, characterization json and prediction json) into one study package - that should then make it easy to run the diagnostic before the prediction. Let us know if you have any Ideas for this