Plugin for local coordinate system selectors

[cactorium]

This adds a new plugin that adds 3 new axes to use in selectors, the local X, Y, and Z. It's pretty intrusive on how it monkey patches than how I'd like, and basically uses globals to inject the local axis vectors into the string selector parsing logic, so please let me know if you guys think there's a better way to do it

[jmwright]

It's pretty intrusive on how it monkey patches than how I'd like

A plugin is a good place for something like this. CadQuery users can choose whether or not to use it, and if someone figures out a cleaner way to implement it later, they can submit a PR for your plugin.

@cactorium I have approved the workflows to run. Please let me know when this is ready for final review.

[cactorium]

I think it should be good for final review now

[jmwright]

@cactorium The lint check is still failing. Please be sure you are running the same black version as this plugin repo, which follows the core CQ repo.

pip install git+https://github.com/cadquery/black.git@cq

[cactorium]

Ah, whoops, thank you

EDIT: it looks like that version of black is giving different formatting suggestions than the workflow run, can you confirm that it should be version 0.1.dev631+gef9d467?

[jmwright]

@cactorium The lint check is green now, so I think everything is ok. Thanks for the contribution!