Bump k8s.io/client-go from 0.18.8 to 0.19.1

Bumps [k8s.io/client-go](https://github.com/kubernetes/client-go) from 0.18.8 to 0.19.1.
- [Release notes](https://github.com/kubernetes/client-go/releases)
- [Changelog](https://github.com/kubernetes/client-go/blob/master/CHANGELOG.md)
- [Commits](https://github.com/kubernetes/client-go/compare/v0.18.8...v0.19.1

)
Signed-off-by: dependabot[bot] <support@github.com>

go.mod

@@ -3,13 +3,15 @@ module github.com/weaveworks/kured
 go 1.13
 
 require (
-	github.com/googleapis/gnostic v0.2.0 // indirect
 	github.com/inconshreveable/mousetrap v1.0.0 // indirect
+	github.com/jessevdk/go-flags v1.4.0 // indirect
 	github.com/prometheus/client_golang v0.0.0-20181230203121-fb3d5cb2ad57
 	github.com/prometheus/common v0.0.0-20181218105931-67670fe90761
 	github.com/prometheus/procfs v0.0.0-20190102135031-14fa7590c24d // indirect
 	github.com/sirupsen/logrus v1.2.0
 	github.com/spf13/cobra v0.0.0-20181127133106-d2d81d9a96e2
-	k8s.io/apimachinery v0.18.8
-	k8s.io/client-go v0.18.8
+	k8s.io/apimachinery v0.19.1
+	k8s.io/client-go v0.19.1
+	k8s.io/klog v1.0.0 // indirect
+	sigs.k8s.io/structured-merge-diff/v3 v3.0.0 // indirect
 )