According to Openstack summit session [1],
stestr is maintained project to which all Openstack projects should migrate.
Let's switch to stestr as other projects have already moved to it.
[1] https://etherpad.openstack.org/p/YVR-python-pti
Change-Id: I49de3c0afde9bf3be15b02017031f44bbefcb1e7
'tox -e cover' fails as --coverage-package-name option for 'testr' is
not recognized. A work-around proposed by Infra team (see
https://bugs.launchpad.net/neutron/+bug/1454772) is to replace 'testr'
with 'test'.
This patch implements this change and adds the cover/ directory to
.gitignore.
Change-Id: I659445ea479ea80a4f21d6ebca896abb4fb104f2
Closes-Bug: #1703177