JCBC-177: Added code to support single null in view query

Change-Id: If3b1e2cddda8ddad5d1568d96052347311569d41
Reviewed-on: http://review.couchbase.org/25415
Reviewed-by: Michael Nitschinger <michael.nitschinger@couchbase.com>
Tested-by: Deepti Dawar <deepti.dawar@globallogic.com>