Use Ginkgo Skip() to avoid failing when tests are skipped

- Added util methods: Skipf, SkipUnlessNodeCountIsAtLeast, SkipIfProviderIs,
  and SkipUnlessProviderIs

test/e2e/monitoring.go

@@ -39,14 +39,11 @@ var _ = Describe("Monitoring", func() {
 		var err error
 		c, err = loadClient()
 		expectNoError(err)
+
+		SkipUnlessProviderIs("gce")
 	})
 
 	It("should verify monitoring pods and all cluster nodes are available on influxdb using heapster.", func() {
-		if !providerIs("gce") {
-			By(fmt.Sprintf("Skipping Monitoring test, which is only supported for provider gce (not %s)",
-				testContext.Provider))
-			return
-		}
 		testMonitoringUsingHeapsterInfluxdb(c)
 	})
 })