CBQE-0: add logs

Change-Id: I8ba0e32e90f9256750faef1aa4d138859a63c23e
Reviewed-on: http://review.couchbase.org/27097
Reviewed-by: Iryna Mironava <irynamironava@yandex.ru>
Tested-by: Iryna Mironava <irynamironava@yandex.ru>