Automatic merge from submit-queue

Add NodeName to EndpointAddress object

Adding a new string type `nodeName` to api.EndpointAddress.
We could also do  *ObjectReference to the api.Node object instead, which would be more precise for the future.

```
type ObjectReference struct {
    Kind            string    `json:"kind,omitempty"`
    Namespace       string    `json:"namespace,omitempty"`
    Name            string    `json:"name,omitempty"`
    UID             types.UID `json:"uid,omitempty"`
    APIVersion      string    `json:"apiVersion,omitempty"`
    ResourceVersion string    `json:"resourceVersion,omitempty"`

    // Optional. If referring to a piece of an object instead of an entire object, this string
    // should contain information to identify the sub-object. For example, if the object
    // reference is to a container within a pod, this would take on a value like:
    // "spec.containers{name}" (where "name" refers to the name of the container that triggered
    // the event) or if no container name is specified "spec.containers[2]" (container with
    // index 2 in this pod). This syntax is chosen only to have some well-defined way of
    // referencing a part of an object.
    // TODO: this design is not final and this field is subject to change in the future.
    FieldPath string `json:"fieldPath,omitempty"`
}
```