New methods for connection tester are introduced in this patch. They
send certain amount of icmp packets and then compare the results, so we
succeed in positive tests only when all packets were replied. We succeed
in negative tests only when all packets were lost. Both approaches are
wrapped by actively waiting for successful result so we don't fail in
case where we test connectivity while resources are not wired yet.
This change is a followup to https://review.openstack.org/#/c/335536/ to
improve stability of its functional tests.
Closes-Bug: 1617319
Change-Id: I907ebd790f4ba3b4ecb0dce711c9f7d2c5244765
2618726458