Plugin system for tooling

[kscarlett]

It would be beneficial to have a plugin system to allow for more commands in the core toolset.

This would allow for anyone to create a linter or testing tool, and make it available from the core tools.

The option I'm currently looking at to achieve this with is the plugin package. This comes with one major disadvantage: it does not support Windows currently.

We then have three options:

1. Temporarily discontinue Windows support.
2. Find another way of implementing plugins.
3. Don't implement plugins.

If anyone has an opinion on this, I'd like to hear it.