DynamicResource should be replaced by DynamicObject

[clux]

At the moment the api-discovery system in the client gives you DynamicResources in master.
However, to be turned into an Api, it goes thorugh:

pub fn try_into_api<K: Meta>(self, client: Client) -> Result<Api<K>>

i.e. it requires you having the type K already implementing Meta.
If we instead do this type of impls on DynamicResource, and construct the GVK behind the seems, it seems plausible to me that users can get an Api with a GVK family.

What do you think @MikailBag ?

[clux]

Acceptance goals: dynamic_api example should be extendable so that we can add a dynapi.list() at every stage and print names of everything.
This would give us functionality like kubectl get all --all.

[MikailBag]

it requires you having the type K already implementing Meta.

I think that kube::Api::DynamicObject should work as a K.
I've sent #466 to update dynamic_api example.