failed to run python -m unittest discover tests/unit

[Sergey Skripnick]

Error when trying to run unittests without tox:

python -m unittest discover tests/unit

...

  File "/usr/lib/python2.7/pdb.py", line 61, in <module>
    class Pdb(bdb.Bdb, cmd.Cmd):
AttributeError: 'module' object has no attribute 'Cmd'

All tests failed.

This is happened because of rally.cmd module.

pdb.py has following line:

 import cmd

and in some cases it imports `rally.cmd` instead of standard python's `cmd` module.

This may cause other unexpected errors.

rally.cmd should be renamed. `cli` seems good name for it

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/184591
Committed: https://git.openstack.org/cgit/openstack/rally/commit/?id=a9b635f62e1666e51d7e0cc9b7f5b77c2788e527
Submitter: Jenkins
Branch: master

commit a9b635f62e1666e51d7e0cc9b7f5b77c2788e527
Author: Sergey Skripnick <email address hidden>
Date: Wed May 20 22:10:22 2015 +0300

    Rename rally.cmd to rally.cli

    There is module 'cmd' in standard library, and unittest's discover
    does modify sys.path when running tests. This cause errors when running
    unit tests in some environments (E.g. pycharm)

    Change-Id: I4fd2d271da1b7fd300fbbeb6107aa958e716fd2b
    Closes-Bug: 1457162