Modernize the code base

[multani]

• Use attrs instead of attr
• Fully type the code base: mypy and autocompletion tool should work correctly on all the objects and types. Also, deserializing a JSON SARIF file should populate the whole datastructure correctly using cattrs.

[multani]

@microsoft-github-policy-service agree

[malexmave]

Thank you for your work on this. I'm not a maintainer or affiliated with this project, but I'd love to see this merged.

One thing I noticed when looking at your repo: The code blocks in the README.md seem to be badly formatted, as there is no Python syntax highlighting and instead it simply underlines the whole code:

While waiting for a review from the maintainers, you may want to take another look at that :).

[multani]

One thing I noticed when looking at your repo: The code blocks in the README.md seem to be badly formatted, as there is no Python syntax highlighting and instead it simply underlines the whole code.

This is an issue with GitHub itself, sadly :/ github/markup#1796

The README could be turned into a Markdown document instead, perhaps?