CBQE-1531: add precedense queries

Change-Id: I59aea4da513a8a95dd80b4f11b5f155649675726
Reviewed-on: http://review.couchbase.org/29300
Reviewed-by: Ketaki Gangal <ketakigangal@gmail.com>
Tested-by: Iryna Mironava <irynamironava@yandex.ru>