Add pre-commit hook configuration

[Jackenmen]

Adds support for usage with pre-commit

[CagtayFabry]

would be really nice to have this, can you take a look @dzhu ?

[onemec]

@jack1142 would it be possible to push out a new release/tag so that this is usable with pre-commit? Right now, I've been able to get it working by tagging the commit SHA, but the latest release doesn't have it yet.

Also, minor suggestion, but might be nice to add a blurb to the README with an example pre-commit config similar to:

 - repo: https://github.com/dzhu/rstfmt
    rev: de1ae7823e3242402a68202fcb7dee9b2ee17ce7 <--- hoping to replace this with v0.0.12
    hooks:
      - id: rstfmt

and/or adding a .pre-commit-config.yaml similar to Black's example.
Happy to help with this as well, and appreciate the project!

[Jackenmen]

I'm not the project owner.

[onemec]

Ah sorry I meant to tag @dzhu, sorry for the ping.