NCBC-317 Mark Sync operations as obsolete

Change-Id: I28b15eb2ee03681c1e29140742ab3e7bff1a39aa
Reviewed-on: http://review.couchbase.org/29750
Tested-by: Jeffry Morris <jeffrymorris@gmail.com>
Reviewed-by: Matt Ingenthron <matt@couchbase.com>