Define and implement equivalent `k8s-openapi` traits

[clux]

A thing that can be done in parallel to the implementation of the code-generation, is to sketch out the traits we need to implement in the codegen, and whether we need to rethink them a bit.

There is currently a bit of a disparity between k8s-openapi traits and kube_core's traits, and it would be nice if the traits we used in kube, were the traits defined either by kube_core or something here.

So here's a rough list of generics I think we should aim to implement / refine for this project to be successful:

wanted traits

Need at least these two to be able to implement kube::Resource upstream:

• k8s-openapi::ResourceScope equivalent. from old issue Resources are not scoped kube#194 - done in Add scope to the Resource trait #25
• k8s-openapi::Resource equivalent - Add Traits #14 + Add scope to the Resource trait #25

getter traits

• HasSpec and HasStatus: https://github.com/kube-rs/kube-rs/blob/master/kube-core/src/object.rs - Add Traits #14
• HasConditions: needed for things like Generic wait-for-condition Condition kube#679 - Add Traits #14
• HasMetadata :: an analogue of the k8s_openapi::Metadata trait - Add Traits #14
  There are probably room for more things, but we should decide where generics should live.

Here? Or separate repo? I'm leaning towards defining a kube-traits crate within the kube-rs org and implementing it here.
But open to ideas. Also, anything missing from this list?

Descoped

These could maybe be done later for even more generic action.

• verb traits for subresources (e.g. Log - these should probably not live in kube-client)
• verb traits for normal resources - enables neokubism Project Neokubism kube#594

[kazk]

I'm not sure where everything should be yet, but I'll transfer this repo to the org. Protobuf + Generics derived from OpenAPI looks promising to me, and even if we decide to create a new repo after experimenting more in this one, we can always rename this to k8s-pb-archived or something.

[clux]

Updated to reflect progress.