Move from glog to klog

- Move from the old github.com/golang/glog to k8s.io/klog
- klog as explicit InitFlags() so we add them as necessary
- we update the other repositories that we vendor that made a similar
change from glog to klog
  * github.com/kubernetes/repo-infra
  * k8s.io/gengo/
  * k8s.io/kube-openapi/
  * github.com/google/cadvisor
- Entirely remove all references to glog
- Fix some tests by explicit InitFlags in their init() methods

Change-Id: I92db545ff36fcec83afe98f550c9e630098b3135

test/utils/density_utils.go

@@ -21,12 +21,12 @@ import (
 	"strings"
 	"time"
 
-	"github.com/golang/glog"
 	"k8s.io/api/core/v1"
 	apierrs "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
 	clientset "k8s.io/client-go/kubernetes"
+	"k8s.io/klog"
 )
 
 const (
@@ -79,7 +79,7 @@ func RemoveLabelOffNode(c clientset.Interface, nodeName string, labelKeys []stri
 			if !apierrs.IsConflict(err) {
 				return err
 			} else {
-				glog.V(2).Infof("Conflict when trying to remove a labels %v from %v", labelKeys, nodeName)
+				klog.V(2).Infof("Conflict when trying to remove a labels %v from %v", labelKeys, nodeName)
 			}
 		} else {
 			break