- `spec.versions[*].schema.openAPIV3Schema` is now required when creating v1 CustomResourceDefinitions
  - `spec.preserveUnknownFields: true` is disallowed when creating v1 CustomResourceDefinitions; it must be specified within schema definitions as `x-kubernetes-preserve-unknown-fields: true`

//		to appear in #cgo CFLAGS source code directives.
//		Does not apply to the CGO_CFLAGS environment variable.
//	CGO_CFLAGS_DISALLOW
//		A regular expression specifying flags that must be disallowed
//		from appearing in #cgo CFLAGS source code directives.
//		Does not apply to the CGO_CFLAGS environment variable.
//	CGO_CPPFLAGS, CGO_CPPFLAGS_ALLOW, CGO_CPPFLAGS_DISALLOW

</p>
<p>
Implementation restriction: For compatibility with other tools, a
compiler may ignore a UTF-8-encoded byte order mark
(U+FEFF) if it is the first Unicode code point in the source text.
A byte order mark may be disallowed anywhere else in the source.
</p>

<h3 id="Characters">Characters</h3>

<p>
The following terms are used to denote specific Unicode character categories:
</p>
<pre class="ebnf">

specified. The signer defines:\n 1. Trust distribution: how trust (CA bundles) are distributed.\n 2. Permitted subjects: and behavior when a disallowed subject is requested.\n 3. Required, permitted, or forbidden x509 extensions in the request (including whether subjectAltNames are allowed, which types, restrictions on allowed values) and behavior when a disallowed extension is requested.\n 4. Required, permitted, or forbidden key usages / extended key usages.\n 5. Expiration/certificate lifetime: whether...

	//   allows any non-core object, as well as PersistentVolumeClaim objects.
	// * While dataSource ignores disallowed values (dropping them), dataSourceRef
	//   preserves all values, and generates an error if a disallowed value is
	//   specified.
	// * While dataSource only allows local objects, dataSourceRef allows objects
	//   in any namespaces.

and dataSourceRef: * While dataSource only allows two specific types of objects, dataSourceRef\n  allows any non-core object, as well as PersistentVolumeClaim objects.\n* While dataSource ignores disallowed values (dropping them), dataSourceRef\n  preserves all values, and generates an error if a disallowed value is\n  specified.\n* While dataSource only allows local objects, dataSourceRef allows objects\n  in any namespaces.\n(Beta) Using this field requires the AnyVolumeDataSource feature gate to...

        * `[*.]kubelet.kubernetes.io/*`
        * `[*.]node.kubernetes.io/*`
    * Setting other `kubernetes.io/`- and `k8s.io/`-prefixed labels using the `--node-labels` flag will produce a warning in v1.13, and be disallowed in v1.15. Setting labels that are not prefixed with `kubernetes.io/` or `k8s.io/` is still permitted.

          },
          "path": {
            "description": "path is matched against the path of an incoming request. Currently it can contain characters disallowed from the conventional \"path\" part of a URL as defined by RFC 3986. Paths must begin with a '/' and must be present when using PathType with value \"Exact\" or \"Prefix\".",
            "type": "string"
          },

* Access to externally managed IP addresses via the kube-apiserver service proxy subresource is no longer allowed by default. This can be re-enabled via the `ServiceProxyAllowExternalIPs` feature gate, but will be disallowed completely in 1.11 ([#57265](https://github.com/kubernetes/kubernetes/pull/57265), [@brendandburns](https://github.com/brendandburns))

* Access to externally managed IP addresses via the kube-apiserver service proxy subresource is no longer allowed by default. This can be re-enabled via the `ServiceProxyAllowExternalIPs` feature gate, but will be disallowed completely in 1.11 ([#57265](https://github.com/kubernetes/kubernetes/pull/57265), [@brendandburns](https://github.com/brendandburns))