hs-test: add test suite features

Test suite now supports assertions which on fail stop test case run,
also it allows to create docker containers which are going to be
stopped automatically after the test run is finished.

Type: improvement
Signed-off-by: Maros Ondrejicka <maros.ondrejicka@pantheon.tech>
Change-Id: I2834709b1efd17b8182d36cc0404b986b4ed595d
Signed-off-by: Filip Tehlar <ftehlar@cisco.com>