* 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))

		abistr := p.get(scanner.Ident).String()
		if !p.allowABI {
			if issueError {
				p.errorf("ABI selector only permitted when compiling runtime, reference was to %q", name)
			}
		} else {
			theabi, valid := obj.ParseABI(abistr)
			if !valid {
				if issueError {
					p.errorf("malformed ABI selector %q in reference to %q",
						abistr, name)
				}
			} else {
				abi = theabi
			}
		}
	}

  - `create service externalname` ([#34789](https://github.com/kubernetes/kubernetes/pull/34789), [@adohe](https://github.com/adohe))
- `set selector` - update selector labels ([#38966](https://github.com/kubernetes/kubernetes/pull/38966), [@kargakis](https://github.com/kargakis))

b)n.isFunction(this[c])?this[c](b[c]):this.attr(c,b[c]);return this}return d=l.getElementById(c[2]),d&&d.parentNode&&(this.length=1,this[0]=d),this.context=l,this.selector=a,this}return a.nodeType?(this.context=this[0]=a,this.length=1,this):n.isFunction(a)?"undefined"!=typeof y.ready?y.ready(a):a(n):(void 0!==a.selector&&(this.selector=a.selector,this.context=a.context),n.makeArray(a,this))};A.prototype=n.fn,y=n(l);var B=/^(?:parents|prev(?:Until|All))/,C={children:!0,contents:!0,next:!0,prev:!0};n.ex...

* Quota admission configuration api graduated to v1beta1 ([#66156](https://github.com/kubernetes/kubernetes/pull/66156), [@vikaschoudhary16](https://github.com/vikaschoudhary16))

 selector mutation in
 a consistent way. This restriction may be lifted in the future, but
 it is likely that that selectors will remain immutable after the move to v1.
 You can continue to use code that depends on mutable selectors by calling
 the apps/v1beta1 API in this release, but you should start planning for code
 that does not depend on mutable selectors.

### **Security**
#### Admission Control
* [alpha] Add [extensible external admission control](https://kubernetes.io/docs/admin/extensible-admission-controllers/).

#### TLS Bootstrapping

- Added ListMeta.RemainingItemCount. When responding to a LIST request, if the server has more data available, and if the request does not contain label selectors or field selectors, the server sets the ListOptions.RemainingItemCount to the number of remaining objects. ([#75993](https://github.com/kubernetes/kubernetes/pull/75993), [@caesarxuchao](https://github.com/caesarxuchao))

[d]||{},p=u[d=(r?f.delegateType:f.bindType)||d]||[],s=s[2]&&new RegExp("(^|\\.)"+h.join("\\.(?:.*\\.|)")+"(\\.|$)"),a=o=p.length;while(o--)c=p[o],!i&&g!==c.origType||n&&n.guid!==c.guid||s&&!s.test(c.namespace)||r&&r!==c.selector&&("**"!==r||!c.selector)||(p.splice(o,1),c.selector&&p.delegateCount--,f.remove&&f.remove.call(e,c));a&&!p.length&&(f.teardown&&!1!==f.teardown.call(e,h,v.handle)||ce.removeEvent(e,d,v.handle),delete u[d])}else for(d in u)ce.event.remove(e,d+t[l],n,r,!0);ce.isEmptyObject...

    * setting `KUBE_PROXY_DAEMONSET=true` in kube-up will now set a `node.kubernetes.io/kube-proxy-ds-ready=true` label on new nodes. In v1.16, the kube-proxy daemonset add-on will switch to using that label as a node selector.
    * In 1.16, the masq-agent daemonset add-on will switch to using `node.kubernetes.io/masq-agent-ds-ready` as a node selector.