added OpenShifts fork of Kubernetes

reason for this is that openshift/kubernetes backported
k8s.io/kubernetes/pkg/securitycontextconstraints/util
that is currently required by something that
github.com/openshift/origin/pkg/deploy/api/v1 depends on

vendor/github.com/openshift/origin/pkg/api/extension/extension.go

@@ -0,0 +1,104 @@
+package extension
+
+import (
+	"fmt"
+
+	"k8s.io/kubernetes/pkg/conversion"
+	"k8s.io/kubernetes/pkg/runtime"
+)
+
+// Convert_runtime_Object_To_runtime_RawExtension attempts to convert runtime.Objects to the appropriate target, returning an error
+// if there is insufficient information on the conversion scope to determine the target version.
+func Convert_runtime_Object_To_runtime_RawExtension(c runtime.ObjectConvertor, in *runtime.Object, out *runtime.RawExtension, s conversion.Scope) error {
+	if *in == nil {
+		return nil
+	}
+	obj := *in
+
+	switch obj.(type) {
+	case *runtime.Unknown, *runtime.Unstructured:
+		out.Raw = nil
+		out.Object = obj
+		return nil
+	}
+
+	switch t := s.Meta().Context.(type) {
+	case runtime.GroupVersioner:
+		converted, err := c.ConvertToVersion(obj, t)
+		if err != nil {
+			return err
+		}
+		out.Raw = nil
+		out.Object = converted
+	default:
+		return fmt.Errorf("unrecognized conversion context for versioning: %#v", t)
+	}
+	return nil
+}
+
+// Convert_runtime_RawExtension_To_runtime_Object attempts to convert an incoming object into the
+// appropriate output type.
+func Convert_runtime_RawExtension_To_runtime_Object(c runtime.ObjectConvertor, in *runtime.RawExtension, out *runtime.Object, s conversion.Scope) error {
+	if in == nil || in.Object == nil {
+		return nil
+	}
+
+	switch in.Object.(type) {
+	case *runtime.Unknown, *runtime.Unstructured:
+		*out = in.Object
+		return nil
+	}
+
+	switch t := s.Meta().Context.(type) {
+	case runtime.GroupVersioner:
+		converted, err := c.ConvertToVersion(in.Object, t)
+		if err != nil {
+			return err
+		}
+		in.Object = converted
+		*out = converted
+	default:
+		return fmt.Errorf("unrecognized conversion context for conversion to internal: %#v (%T)", t, t)
+	}
+	return nil
+}
+
+// DecodeNestedRawExtensionOrUnknown
+func DecodeNestedRawExtensionOrUnknown(d runtime.Decoder, ext *runtime.RawExtension) {
+	if ext.Raw == nil || ext.Object != nil {
+		return
+	}
+	obj, gvk, err := d.Decode(ext.Raw, nil, nil)
+	if err != nil {
+		unk := &runtime.Unknown{Raw: ext.Raw}
+		if runtime.IsNotRegisteredError(err) {
+			if _, gvk, err := d.Decode(ext.Raw, nil, unk); err == nil {
+				unk.APIVersion = gvk.GroupVersion().String()
+				unk.Kind = gvk.Kind
+				ext.Object = unk
+				return
+			}
+		}
+		// TODO: record mime-type with the object
+		if gvk != nil {
+			unk.APIVersion = gvk.GroupVersion().String()
+			unk.Kind = gvk.Kind
+		}
+		obj = unk
+	}
+	ext.Object = obj
+}
+
+// EncodeNestedRawExtension will encode the object in the RawExtension (if not nil) or
+// return an error.
+func EncodeNestedRawExtension(e runtime.Encoder, ext *runtime.RawExtension) error {
+	if ext.Raw != nil || ext.Object == nil {
+		return nil
+	}
+	data, err := runtime.Encode(e, ext.Object)
+	if err != nil {
+		return err
+	}
+	ext.Raw = data
+	return nil
+}