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* Update docs/submodules/yardstick from branch 'master'
  - Add "restartPolicy" parameter in Kubernetes policy

    This new parameter, "restartPolicy", will allow define the restart policy per pod.

    Example of yaml definition in Kubernetes:
    apiVersion: v1
    kind: Pod
    metadata:
      name: frontend
    spec:
      containers:
        - name: db
          ...
      restartPolicy: Always  # Possible values: "Always", "OnFailure" and "Never"

    Example of definition in a Yardstick context:
    context:
      type: Kubernetes
        servers:
          host:
            containers:
              - name: ...
            restartPolicy: Always  # Default value: "Always"

    Restart policy [1].
    [1] https://kubernetes.io/docs/concepts/workloads/pods/pod-lifecycle/#restart-policy

    JIRA: YARDSTICK-1175

    Change-Id: Id4317b909f98422e89d6d4553e8cfb0e1f593355
    Signed-off-by: John O Loughlin <john.oloughlin@intel.com>