CBQE-0: add logs

Change-Id: I1cc2e69514ba775c6f40dcd92057ffd257811209
Reviewed-on: http://review.couchbase.org/27286
Reviewed-by: Iryna Mironava <irynamironava@yandex.ru>
Tested-by: Iryna Mironava <irynamironava@yandex.ru>