[cern] Update k8s to 1.5.2

Following up the cherry-pick for k8s 1.4.7 [1] and fix for docker-storage-setup [2], update k8s version to 1.5.2.

[1] https://gitlab.cern.ch/cloud-infrastructure/magnum/commit/280096fce4053579b4baf1c4808a6aecd95af054 [2] https://gitlab.cern.ch/cloud-infrastructure/magnum/commit/eb5cd5186fcbb9a7e505c2a40e09bcd25b242e0c

magnum/drivers/k8s_fedora_atomic_v1/templates/kubecluster.yaml

@@ -262,7 +262,7 @@ parameters:
   kube_version:
     type: string
     description: version of kubernetes used for kubernetes cluster
-    default: v1.4.7
+    default: v1.5.2
 
   insecure_registry_url:
     type: string