Updated openstack/openstack
Project: openstack/python-ceilometerclient  6d797aaced6334fa405c623bc5ba01207c4d5e33

Add --slowest option for testr

Enable --slowest option for testr, so we can observe the worst
performance unit test cases of all.

Change-Id: I7a5ce4b44a3571da9156a37657d16c8a2f468319