CBQE-1797: add slicing test

Change-Id: I33025e0b2bba8ea96898509a8c11cb60d37e03e9
Reviewed-on: http://review.couchbase.org/31266
Reviewed-by: Iryna Mironava <irynamironava@yandex.ru>
Tested-by: Iryna Mironava <irynamironava@yandex.ru>