Add the donation checklist to the repo guidelines

[rgregg]

There's a nice donation checklist that a few people have used in their Issues to donate code to the Knative project. However, this template and the actions required by it are not spelled out anywhere in the repo guidelines.

We should clean that up into a documented process, instead of a shared knowledge thing.

[mattmoor]

So... This actually is spelled out (as we discovered Thursday), and it's not that list :)

https://github.com/knative/community/blob/master/REPOSITORY-GUIDELINES.md#requirements-for-repository-donation

[mattmoor]

I think it's worth leaving this open to make it more discoverable, but it exists.

[rgregg]

I think the guidelines are insufficient, and hence why that checklist grew organically out of previous requests. E.g. there's nothing in the documented guidelines about Steering having a voice about a fit to project scope. The documented steps are a very tactical "do this than that" kind of thing, without the strategic/project elements included, which are more visible in the checklist.

I'd like to see us combine elements of the checklist into what we've documented, and ideally give that checklist in markdown that people can include in their request. Perhaps an Issue template?

[rgregg]

Also, we shouldn't leave issues open to fix discoverability problems.

[mattmoor]

I meant leave it open to track FIXING the discoverability issues 😉

[pmorie]

I think we are close to having this closed by #151

[vaikas]

/close