Add Conda & Pixi installation method

[claudiushaag]

I added dooit to conda-forge, so it is installable using Pixi, which fits my workflow well.
The dooit-extras feedstock is currently under review ready!

I also updated the installation hints, hence the PR.

@kraanzu Would also be happy to add you or someone else as a maintainer on the feedstock, if you like.

[kraanzu]

Hi @claudiushaag, Thanks for the contrubtion. Sorry for the delayed response, I've been a lot busy with other stuff.
Never heard about pixi, will check it out :)

Would also be happy to add you or someone else as a maintainer on the feedstock

Maybe add me as a co-maintainer? I'd check out the packaging stuff (feel free to share a good resource)

[claudiushaag]

No worries!
I love using 'pixi global' for independent python environments with specific exposed executables. This makes installation and updating of those very easy and keeps everything in one place.
You can check out the docs on how to use it.

I will add you to the feedstocks, so you have the ability to update the versions (which will be an automatically opened PR on that Repo, when an update on PyPi is detected). I will continue to support and maintain there.