Don't use deprecated module commands

The commands module was deprecated since version 2.6 and it has been
removed in Python 3. This patch uses processutils.trycmd method to
replace of deprecated module commands.
See http://docs.python.org/2/library/commands#module-commands

Closes-Bug: #1248216

Change-Id: Iee0b3cf59c738bfda9c5b2049a1853abbb6d16e0
Clean up extra modules code

The config generator extra modules code was attempting to look up
an empty module name if extra modules were not specified.  This
resulted in a spurious exception.

This change also strips the module names so extra spaces in the
env var won't cause problems.

Change-Id: I4cfbeb62fc25220ab43d6f80006245be3376dc93
Improve error reporting on import failures

The existing config generator code does not report general errors
importing modules well.  In my case, that meant I had no idea that
an old version of six on my system was causing a module import to
fail.

This change logs all errors importing a module to stderr.

Change-Id: I4663f5bbd4f553c0d6ce5f84b1c1275a7304e3b5
Merge "Clean up extra modules code"
Merge "Improve error reporting on import failures"
Merge "Don't use deprecated module commands"
Remove uuidutils imports in oslo modules

The only use of uuidutils in oslo-incubator is generate_uuid
which could be replaced with uuid.uuid4().
Droping the dependency would help deprecating/removing uuidutils
in the future.

Partial-bug: #1253497

Change-Id: Ie0bc94e0b4aea6563f138c0f09c54c323ba23279
Remove vim header

No need to set tabstop 189 times, this can be set in your vimrc file
instead.  Also if set incorrectly gate (pep8 check) will catch your
mistakes.

Change-Id: Ic6f0c0ef94e8194a5c121598305d1ec3c74e4843