Misc outstanding queries / ideas

[ ] Can we move calculation from BQ to postgres?
[ ] Formulation swap spreadsheets should be frozen by date
[ ] Add dm&d downloading commands etc to openprescribing-data
[ ] Add an upload-to-bigquery step for dmd_product
[ ] dmd needs a date field for the tariff stuff (at least); probably a date field for every table

ebmdatalab / price-per-dose