tox is not working as works in other projects

[Surya Prakash Singh]

tox -e cover

https://www.irccloud.com/pastebin/jxBQuHXF/

tox -e py35

https://www.irccloud.com/pastebin/WK4jgcfc/

Bug easily reproducible by following below steps :-

clone the new kolla-kubernetes repo and run the above commands.

==========================================================================
Traceback (most recent call last):
  File "/home/spsingh/workplace/kolla-kubernetes/kolla_kubernetes/tests/test_templates.py", line 189, in test_validate_templates
    on_each_template(func)
  File "/home/spsingh/workplace/kolla-kubernetes/kolla_kubernetes/tests/test_templates.py", line 72, in on_each_template
    '', 'resource-template')
  File "/home/spsingh/workplace/kolla-kubernetes/.tox/py35/lib/python3.5/site-packages/cliff/command.py", line 46, in __init__
    self._load_hooks()
  File "/home/spsingh/workplace/kolla-kubernetes/.tox/py35/lib/python3.5/site-packages/cliff/command.py", line 52, in _load_hooks
    self.app.command_manager.namespace,
AttributeError: 'str' object has no attribute 'command_manager'
Ran 22 tests in 27.891s (-0.114s)
FAILED (id=2, failures=1)
error: testr failed (1)
ERROR: InvocationError: "/bin/bash -c tools/test.sh ''"
______________________________________________________________ summary _______________________________________________________________
ERROR: py35: commands failed
===========================================================================

[Surya Prakash Singh (confisurya)]

Fix released in https://review.openstack.org/#/c/483097/1 but not been associated with bug id