Update kubernetes config for 1.15 features.

Upgrading from kubernetes 1.13.5 to 1.15.0 meant the config
needed to be updated to handle whatever was deprecated or dropped
in 1.14 and 1.15.

1) Removed "ConfigMapAndSecretChangeDetectionStrategy = Watch"
reported by kubernetes/kubernetes#74412
because this was a golang deficiency, and is fixed by the newer
version of golang.

2) Enforced the kubernetes 1.15.3 version

3) Updated v1alpha3 to v1beta2, since alpha3 was dropped in 1.14
changed fields for beta1 and beta2 are mentioned in these docs:
https://godoc.org/k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta1
https://godoc.org/k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta2

4) cgroup validation checking now includes the pids subfolder.

5) Update ceph-config-helper to v1.15 kubernetes compatable
This means that the stx-openstack version check needed to be increased

Change-Id: Ibe3d5960c5dee1d217d01fbb56c785581dd1b42c
Story: 2005860
Task: 35841
Depends-On: https://review.opendev.org/#/c/671150
Signed-off-by: Al Bailey <Al.Bailey@windriver.com>

stx-platform-helm/stx-platform-helm/helm-charts/ceph-pools-audit/values.yaml

@@ -26,7 +26,7 @@ conf:
 
 images:
   tags:
-    ceph_config_helper: docker.io/port/ceph-config-helper:v1.10.3
+    ceph_config_helper: docker.io/starlingx/ceph-config-helper:v1.15.0
   pullPolicy: "IfNotPresent"
   local_registry:
     active: false

stx-platform-helm/stx-platform-helm/helm-charts/rbd-provisioner/values.yaml

@@ -165,7 +165,7 @@ ephemeral_pools:
 images:
   tags:
     rbd_provisioner: quay.io/external_storage/rbd-provisioner:v2.1.1-k8s1.11
-    rbd_provisioner_storage_init: docker.io/port/ceph-config-helper:v1.10.3
+    rbd_provisioner_storage_init: docker.io/starlingx/ceph-config-helper:v1.15.0
   pull_policy: "IfNotPresent"
   local_registry:
     active: false