Honor an OpenStack StorageClass management choice
Honor an OpenStack StorageClass management choice

When choosing a default value for the Cluster spec's
"cloudConfig.manageStorageClasses" field, first check whether a user
specified a concrete value for the related OpenStack
"blockStorage.createStorageClass" field. If so, use that value as the
effective default value for the former field as well, so as to avoid
an unnecessary conflict between the field values on the second
validation pass.

kubernetes/kops,justinsb/kops,kubernetes/kops,justinsb/kops,kubernetes/kops,justinsb/kops