[GUI-21] Refactor ViewportResultsJsonWriter to write both JSON and CSV for viewport results
[GUI-21] Add text/csv string and media type
[GUI-21] Add method to calc result for all grid data and return View definition id
[GUI-21] Add valuation time to result cache
[GUI-21] Create simple analytic view with a View definition Id
[GUI-21] Create viewport results with last valuation time stored in the cache
[GUI-21] Add rest endpoint to save grid results as csv