* Moved pkg/api and pkg/apis to [k8s.io/api](https://github.com/kubernetes/api). Other kubernetes repositories also import types from there, so they are composable with client-go.
* Removed helper functions in pkg/api and pkg/apis. They are planned to be exported in other repos. The issue is tracked [here](https://github.com/kubernetes/kubernetes/issues/48209#issuecomment-314537745). During the transition, you'll have to copy the helper functions to your projects.
* The discovery client now fetches the protobuf encoded OpenAPI schema and returns `openapi_v2.Document`
* The generic RESTClient type (`k8s.io/client-go/rest`) no longer exposes `LabelSelectorParam` or `FieldSelectorParam` methods - use `VersionedParams` with `metav1.ListOptions` instead. The `UintParam` method has been removed. The `timeout` parameter will no longer cause an error when using `Param()`.
* Added mutation cache filter: MutationCache is able to take the result of update operations and stores them in an LRU that can be used to provide a more current view of a requested object.
* PortForwarder: don't log an error if net.Listen fails. [https://github.com/kubernetes/kubernetes/pull/44636](https://github.com/kubernetes/kubernetes/pull/44636)
* oidc auth plugin not to override the Auth header if it's already exits. [https://github.com/kubernetes/kubernetes/pull/45529](https://github.com/kubernetes/kubernetes/pull/45529)
* The --namespace flag is now honored for in-cluster clients that have an empty configuration. [https://github.com/kubernetes/kubernetes/pull/46299](https://github.com/kubernetes/kubernetes/pull/46299)
* Use OS-specific libs when computing client User-Agent in kubectl, etc. (https://github.com/kubernetes/kubernetes/pull/44423)
* kubectl commands run inside a pod using a kubeconfig file now use the namespace specified in the kubeconfig file, instead of using the pod namespace. If no kubeconfig file is used, or the kubeconfig does not specify a namespace, the pod namespace is still used as a fallback. (https://github.com/kubernetes/kubernetes/pull/44570)
* Restored the ability of kubectl running inside a pod to consume resource files specifying a different namespace than the one the pod is running in. (https://github.com/kubernetes/kubernetes/pull/44862)
* Added dependency on k8s.io/apimachinery. The impacts include changing import path of API objects like `ListOptions` from `k8s.io/client-go/pkg/api/v1` to `k8s.io/apimachinery/pkg/apis/meta/v1`.
* Added generated listers (listers/) and informers (informers/)
