Add fields to schema that provide for notes during the review / publish workflow

[njhoebel]

May need notes for each "persona" in the workflow, but TBD how many there will be. E.g., Submitter(?) Reviewer Editor Admin(?)

[hbarrett]

We will put these as an array of strings with the format : "Date:\<datetime>, User:\<username>,Role:\<role>,Note:\<note>"