adding contributing guidance

[MathewBiddle]

@ocefpaf can you check for any inconsistencies?

[ocefpaf]

Minor comments but LGTM!

[MathewBiddle]

@ocefpaf, I made the change master -> main in the docs, but we should update the repository too. Not sure what the impacts might be (links and refs).

[ocefpaf]

@ocefpaf, I made the change master -> main in the docs, but we should update the repository too. Not sure what the impacts might be (links and refs).

Doing it now. We can fix the links as we go but you will need to update your fork and use main instead of master in the future.

[ocefpaf]

Done! You will have to issue these commands locally on your fork/clone:

git branch -m master main
git fetch origin
git branch -u origin/main main
git remote set-head origin -a

You will also need to rename it in your fork to avoid confusion. GH should have the instructions on your fork when you navigate to it but let me know if you need any help navigating that.

[MathewBiddle]

Thanks @ocefpaf, think I got it situated now.