Fix default NFS mount in Cloud Controller template

The BOSH Job for the Cloud Controller puts the default fog connection as
  provider: Local
  local_root: /var/vcap/nfs/store

Recent commits have caused this location to no longer be writeable by the Cloud Controller; with the new NFS share being located at /var/vcap/nfs/shared

To keep people from having to specify this in the manifest; it's best if we make the default spec correct.