refactoring scrapers/package.py

[duck-master]

This does three things:

• Refactoring scrapers/package.py extensively by splitting off the run() function into two helper functions, namely load_json_data and merge_datasets.
• Creating an empty overrides.json file. (Previously, in Move overrides from scrapers/package.py into a separate file, scrapers/overrides.json #76 there had been a substantial set of overrides, but since the resulting code didn't work due to further commits upstream, I abandoned it.)
• Rewriting README.md accordingly

[duck-master]

also happy thanksgiving btw :P

[psvenk]

Looks good to me; thanks for the PR (and sorry for breaking your previous one :/).

I've come around to agreeing with you that it would be good to split off the overrides into a separate file that is in an actual data format rather than being a Python module.

Part of me still does want to use TOML instead of JSON, though, to make the overrides file more easily human-writable. Since Python 3.11 comes with a TOML reader, I feel like TOML is mainstream enough now that we wouldn't have to worry about it being too bespoke (but we would need to use an external package to maintain compatibility with older Python versions). What are your thoughts?

Happy Thanksgiving to you too!