Add a report API for Spreadsheet models Merged

Spreadsheet models are lacking a proper report API to make them useful in automated reports / workflows.

Add a report API to access the Spreadsheet models as an actual spreadsheet so you can:

Create / delete / edit them via reports

Access single cells / columns / rows so you can read from them and write to them

Add formulas to cells

Add objects to the cells

etc. ...

Basically something like the report APIs present for Excel files, but for Spreadsheet models.