* make docker-checker more robust ([#23662](https://github.com/kubernetes/kubernetes/pull/23662), [@ArtfulCoder](https://github.com/ArtfulCoder))
* validate that daemonsets don't have empty selectors on creation ([#23530](https://github.com/kubernetes/kubernetes/pull/23530), [@mikedanese](https://github.com/mikedanese))

  - [alpha] Alpha level support for DaemonSets in federation. ([docs](http://kubernetes.io/docs/user-guide/federation/daemonsets/)) ([kubernetes/features#101](https://github.com/kubernetes/enhancements/issues/101))

## Changes by Kind

### Deprecation

#### kube-apiserver:
- the following deprecated APIs can no longer be served:
  - All resources under `apps/v1beta1` and `apps/v1beta2` - use `apps/v1` instead
  - `daemonsets`, `deployments`, `replicasets` resources under `extensions/v1beta1` - use `apps/v1` instead
  - `networkpolicies` resources under `extensions/v1beta1` - use `networking.k8s.io/v1` instead

* restore ability to run against secured etcd ([#21535](https://github.com/kubernetes/kubernetes/pull/21535), [@AdoHe](https://github.com/AdoHe))

### Other notable changes

* validate that daemonsets don't have empty selectors on creation ([#23530](https://github.com/kubernetes/kubernetes/pull/23530), [@mikedanese](https://github.com/mikedanese))

* Fix a bug that caused invalid Tolerations to be applied to Pods created by DaemonSets. ([#45349](https://github.com/kubernetes/kubernetes/pull/45349), [@gmarek](https://github.com/gmarek))

- DaemonSets accept a MaxSurge integer or percent on their rolling update strategy that will launch the updated pod on nodes and wait for those pods to go ready before marking the old out-of-date pods as deleted. This allows workloads to avoid downtime during upgrades when deployed using DaemonSets. This feature is alpha and is behind the DaemonSetUpdateSurge feature gate. ([#96441](https://github....

- The `kubectl top` command now includes a `--sort-by` option to sort by `memory` or `cpu`. ([#75920](https://github.com/kubernetes/kubernetes/pull/75920), [@artmello](https://github.com/artmello))
- `kubectl rollout restart` now works for DaemonSets and StatefulSets. ([#77423](https://github.com/kubernetes/kubernetes/pull/77423), [@apelisse](https://github.com/apelisse))

Major features for stateful applications include automated updates to StatefulSets, enhanced updates for DaemonSets, a burst mode for faster StatefulSets scaling, and (alpha) support for local storage.

## Deprecations and Removals

- API

  - The following APIs are no longer served by default:

    - All resources under `apps/v1beta1` and `apps/v1beta2` - use `apps/v1` instead
    - `daemonsets`, `deployments`, `replicasets` resources under `extensions/v1beta1` - use `apps/v1` instead
    - `networkpolicies` resources under `extensions/v1beta1` - use `networking.k8s.io/v1` instead

- Previous versions of Kubernetes on Google Cloud required that workloads (e.g. Deployments, DaemonSets, etc.) which used `PersistentDisk` volumes were using them in read-only mode.  This validation provided very little value at relatively host implementation cost, and will no longer be validated.  If this is a problem for a specific use-case, please...