JCBC-494: Add support for unlock and touch

Change-Id: Id5289d2cd54337e6f6c2628ae5ab063e9f8b0fa1
Reviewed-on: http://review.couchbase.org/39434
Reviewed-by: Michael Nitschinger <michael.nitschinger@couchbase.com>
Tested-by: Michael Nitschinger <michael.nitschinger@couchbase.com>