data(cases-deaths): new tool to inject data from the WHO

[lucasrodes]

central issue: #2785

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This PR aims to provide a new set of tools to keep updating our case and death data. In short, the idea is that the command tool cowid jhu is replaced by cowid casedeath, which should serve the exact same purpose.

This PR will not remove all jhu-related tools and cron jobs. These will continue to run in parallel as the new ones are implemented and improved. This way, we can smoothly transition.

To this end, we need to:

• Add a new module cowid.cases_deaths, with a similar structure as cowid.jhu, that does the same things: Create the necessary files to update our Grapher dataset and our complete dataset (via cowid megafile). We need:
  • Code in cowid.cases_deaths to download, process and export the cases/deaths data.
  • Country standardisation JSON file.
  • New paths added to cowid.PATHS.
  • New timestamp.
• Create a new directory public/data/cases_deaths, to store the output from the previous step.
• Add a new command cowid casedeath: This should replace cowid jhu in the future.
• Add the new methods to our cron jobs:
  • Call cowid casedeath in our autoupdate.sh script, so the new files are generated daily and pushed to the repository.
  • Add the appropriate command to our grapherupdate.sh script, so that the Grapher dataset is updated daily.