cephfs-provisioner: Upgrade to 06fddbe2

-   cephfs-provisioner 06fddbe2 (https://github.com/kubernetes-incubator/external-storage/tree/06fddbe2/ceph/cephfs)

Noteable changes from upstream:

-   Added storage class parameters to specify a root path within the backing cephfs and, optionally, use deterministic directory and user names (https://github.com/kubernetes-incubator/external-storage/pull/696)
-   Support capacity (https://github.com/kubernetes-incubator/external-storage/pull/770)
-   Enable metrics server (https://github.com/kubernetes-incubator/external-storage/pull/797)

Other noteable changes:

-   Clean up legacy manifests file naming
-   Remove legacy manifests, namespace and storageclass before upgrade
-   `cephfs_provisioner_monitors` simplified as string
-   Default to new deterministic naming
-   Add `reclaimPolicy` support in StorageClass

With legacy non-deterministic naming style (where $UUID are generated ramdonly):

-   cephfs_provisioner_claim_root: /volumes/kubernetes
-   cephfs_provisioner_deterministic_names: false
-   Generated CephFS volume: /volumes/kubernetes/kubernetes-dynamic-pvc-$UUID
-   Generated CephFS user: kubernetes-dynamic-user-$UUID

With new default deterministic naming style (where $NAMESPACE and $PVC are predictable):

-   cephfs_provisioner_claim_root: /volumes
-   cephfs_provisioner_deterministic_names: true
-   Generated CephFS volume: /volumes/$NAMESPACE/$PVC
-   Generated CephFS user: k8s.$NAMESPACE.$PVC