build: document & improve release process

[robbat2]

Document & automate release process

Closes: #213

[stappersg]

Thanks for the Rough release process document.

There is much implied knowledge in it. I think I understand most of it.
Thing I don't understand is if the gh release create _files_ is just an upload (I think it is.)

I will approve the merge request, so we can continue.

P.S.
Point 4a git push and 4b git push --tags.

[stappersg]

release early, release often

[robbat2]

@mpontillo would like input on the tooling please, from the release engineering perspective