Adapt the output format and the submission script to match the new Flu Sight Hub

[dshemetov]

• New submission guidelines
• Old submission guidelines

TODO:

• [x] Make a fork of their repo
• [x] Add our team's metadata file
  • [ ] Finalize the information in the metadata file
• [x] Consider using their location data for population and state abbreviation to state code mapping
• [x] Need to make sure our pipeline outputs in the new new submission format schema
  • [x] forecast_date -> reference_date
  • [x] target has been split into two columns target and horizon, horizon is a number between -1 and 3, where 0 is a nowcast
  • [x] type -> output_type
  • [x] quantile -> output_type_id
  • [x] Direction forecasts will now be submitted in the same file as the quantile forecasts with output_type_id set to pmf