feat: add pre-commit hook config

[VannTen]

This ports client9/misspell#174, with some modifications:

• autofix by default in the pre-commit hook (with -w)
• don't limit on which files the hook is run by default (let users add limits if necessary).
• Add usage documentation

I put v0.6.0 in the docs because I suppose this would be a new minor release, but this can be changed if you only want to put it in a patch release.