Ref:https://review.openstack.org/#/c/311653/
We should use 2.1 as the default nova version now
The API_MIN_VERSION of novaclient has already changed to 2.1
Change-Id: I9ff16cf052556e5d3756f81e02a8e76e8f315df5
Closes-bug: #1588171
this will better isolate the unit tests from the functional tests.
unfortunately, the "integration" tests had to be lumped into the
"unit" tests since we need the separation in testr.conf
Change-Id: Ifd12198c1f90e4e3c951c73bfa1884ab300d8ded