Enable NFS to work as a blobstore on bosh-lite / warden

NOTE: We are now mounting the shared NFS without locking because
we cannot run rpc.statd under linux containers / warden

* add `nfs_server:` section to cloud_controller: > properties:
* set `nfs_server:` attributes in warden infrastructure stub

[#65775236]

Signed-off-by: Aram Price <aprice@pivotallabs.com>
`cloud_controller_jobs_ctl` now mounts NFS blobstore

[#65775236]

Signed-off-by: Aram Price <aprice@pivotallabs.com>