Setup CI/CD properly

[sr229]

The repo doesn't have any test/delivery pipeline in place, therefore, to help the maintainers, I'll be making a pipeline for the project that requires nothing but pushing a tag and creating a new release in GitHub, as well setting up test coverage with reporting.

[aquagoose]

Publishing is done with the PublishNuget.sh script. I've set this up on purpose as currently I don't plan to release every GH release to nuget. Pie is primarily still designed to be included directly into your project and will remain that way until 1.0.

[aquagoose]

I do think that having the automatic publish to nuget is a good idea, and I will get around to it probably when 1.0 is nearly released, assuming someone doesn't do it beforehand.