Remove unused variables in test_conductor.py

There are two variables in test_conductor.py that are not used
by anyone, just remove it.

Change-Id: I5086c02004aa70f2393ee3f5a8e25609cc466afa
Add apache2 license header to appropriate files for enabling H102

Apache2 license says that each source file should include the license
header. However, some non empty files don't have it. And we already have
a hacking rule (H102) for this.
This commit fixes them and enables the rule.

Change-Id: I68fa0e1ee43ed28d6b470c0ffff963c095be8283
Don't use deprecated module commands

The commands module was deprecated since version 2.6 and it has been
removed in Python 3.

See http://docs.python.org/2/library/commands#module-commands

Closes-Bug: #1248216
Change-Id: I0ae40c7683ca58ede75f493d020e5c80a6434fef
Imagecache: fix docstring

Original docstring had incorrect information. That is,
the method did not return None.

Change-Id: I7519259b99e21e24723c566e8e7d04e32e0d2c07
platform independence for test_virt unit tests

Uses mock to avoid direct use of /proc file system
in the unit tests. This makes these tests platform
independent.

Change-Id: I21986681a9a1a6db516957246b71d7fd2055d44b
Sync oslo db.sqlalchemy.utils to nova

Changes from oslo-incubator:
===============================

Change I9c441d26: Use single meta when change column type
Change Id6cf7b12: Helper function to sanitize db url credentials
Change I34000ad2: Add function drop_unique_constraint()
Change I292ec445: Change sqlalchemy/utils.py mode back to 644
Change Ia0366dbd: Raise ValueError if sort_dir is unknown
Change Ie54fcd5d: Migrate sqlalchemy utils from Nova

Change-Id: Ia84de322cf9dcf30624ce64f373274ca2e13ae14
Merge "Don't use deprecated module commands"
Merge "platform independence for test_virt unit tests"
Merge "Remove unused variables in test_conductor.py"
Merge "Sync oslo db.sqlalchemy.utils to nova"
Merge "Imagecache: fix docstring"
Merge "Add apache2 license header to appropriate files for enabling H102"