Code formatting and pre-commit hooks

[stefsmeets]

Dianna runs a fairly strict pylint configuration that is somewhat complainy. It's also slow, which makes it a bit of a chore to run while doing the prospector/pylint dance.

Many of the issues it raises are easily fixed by using code formatters like autopep8, yapf, or black. I would be happy to configure one of these (yapf or autopep8 would be my choice) for dianna for code consistency and saving my time.

I'm not in favour of running too many linters/formatters locally, like the documentation recommends. And the pre-commit hook hides the output and requires some manual steps to apply the fixes.

There is an excellent tool called pre-commit that makes it very easy to configure different checks, with automated fixes and it only runs on the code that has been changed. If you agree, I will happily configure it for dianna to run one of the autoformatters above, as well as pylint/pycodestyle.

[cwmeijer]

This would be great and will save us a lot of time for sure.