procedure or derive macro to define Kubernetes API

[sehz]

Instead of manual trait implementation like below:

// Secret Object
const SECRET_API: Crd = Crd {
    group: "core",
    version: "v1",
    names: CrdNames {
        kind: "Secret",
        plural: "secrets",
        singular: "secret",
    },
};

impl Spec for SecretSpec {

    type Status = SecretStatus;
    type Header = SecretHeader;

    fn metadata() -> &'static Crd {
        &SECRET_API
    }
}

We can write procedure macro:

#[k8spec(group=core,status=SecretStatus)]
struct SecretSpec {
}

struct SecretStatus{}