Deleting a namespace is insufficient to cleanup in e2e

Graceful deletion requires more time to terminate namespaces, and not
waiting for namespaces to delete causes scheduling errors

test/e2e/persistent_volumes.go

@@ -46,7 +46,7 @@ var _ = Describe("[Skipped] persistentVolumes", func() {
 
 	AfterEach(func() {
 		By(fmt.Sprintf("Destroying namespace for this suite %v", ns))
-		if err := c.Namespaces().Delete(ns); err != nil {
+		if err := deleteNS(c, ns); err != nil {
 			Failf("Couldn't delete ns %s", err)
 		}
 	})