Ceph for Kubernetes

follow :
https://github.com/kubernetes-incubator/external-storage/

Straight forward with some modifications, as the claim has to have a different name, and pay attention that for CephFS and RDB, the admin secret name is different, but can be set the same.

I also used the same cephfs namespace for both.

EDIT : I made a PR that uses now the same kubernetes user for both storageclass
here : https://github.com/kubernetes-incubator/external-storage/pull/1306