Added Balance Pool Group data for Cardano

[Cerkoryn]

All Submissions:

• [x] Have you followed the guidelines in our Contributing documentation?
• [x] Have you verified that there aren't any other open Pull Requests for the same update/change?
• [ ] Does the Pull Request pass all tests?

Description

I added a different data source using Balance's Pool Group API available here. The Public API available at the bottom of the page provides a more conservative grouping of Cardano Pool Groups that is in line with other community tools such as Cexplorer. The script I used for obtaining and parsing the data is in the cardano_preprocessing folder as get_cardano_info_balance.py. By default the script will save the identifier and cluster files within that subfolder to prevent overwriting, but cardano_pool_data.json will get overwritten.

Additionally, I made minor changes in a few other files to assist with UTF-8 encoding issues. A slightly more impactful change was made in gini.py to prevent an integer overflow issue I was running into. However, this seems to have caused test_analyze.py to fail. I was not able to run the consensus tool for Dogecoin without this change though, so feel free to ignore it or any of the others if necessary.

Checklist

Update Mapping Support Information Submissions:

• For which ledger do you update the mapping information?
  • [x] Cardano
• What mapping information do you update?
  • [x] identifiers
  • [x] addresses
  • [x] clusters
  • [ ] legal links
• [ ] Did you update the tests (if needed)?