Update nfs driver doc for snapshot support
nfs snapshot was supported since ocata, remove the outdated
description
@@ -131,7 +131,6 @@ This example assumes access to the following NFS servers and mount points:
volume-a8862558-e6d6-4648-b5df-bb84f31c8935
This volume can also be attached and deleted just like other volumes.
-However, snapshotting is **not** supported.
NFS driver notes
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