Add a Release Pipeline

[Aragas]

It should do the following things:

• Publish to NuGet
• Publish to GPR (GitHub Package Registry)
• Publish to GitHub Releases

The only question is, how the release should be triggered:

• Manual Workflow Trigger
• On Git Tag added
• On merging anything to master (we'll have to move development to a dev branch then)

[Banane9]

For my personal projects, I've set it up to trigger on pushing a v... tag