NUnit Console/Engine v4

We've talked casually about several changes we'd like to make in v4 over the years - but there's never yet been an important enough breaking change to justify a new major version. Most of our big projects currently seem to be possible in a backwards-compatible fashion. My view however is that the .NET Core changes are starting to create these, and it might be time to start thinking about the future.

I'd like to start tracking changes we'd like to make in v4 - I've created the v4 milestone to do that. Consider this an open invite to anyone to put in issues against v4! 😄 For now, let's just go with tracking them - in future we might create a v4 branch, but I don't want to introduce the overhead of having to keep two branches in sync until we need to.

For issues under 'v4', I'd like to mainly target them towards breaking changes - new features that could be done in a backwards-compatible way in v3 seem much better not to be delayed, and tracked as normal issues. Ultimately I don't see v4 being a 'big bang' release - more a well-curated group of minor breaking changes, to make our lives easier and allow us to move quicker in future.

Thoughts very welcome. 🙂

No files, tests, or code entry points are named. Start by reviewing the v4 milestone and related issues, then determine which proposed breaking changes belong in a curated v4 release; done means the relevant changes are identified and agreed for tracking.