Sync latest Oslo config code for i18n

This sync pulls the latest Oslo config code over
to Cinder.  This sync is needed to include a fix
to config generator which is needed as part of
the work to enabled i18n messages.  Config generator
was failing when lazy message translation was enabled.

The following changes are included with this patch. Each
patch includes the file(s) the patch touches:
-> c178e56 Add basic Python 3 tests
--> cinder/openstack/common/__init__.py
-> 12bcdb7 Remove vim header
--> cinder/openstack/common/__init__.py
-> 547ab34 Fix Copyright Headers - Rename LLC to Foundation
--> cinder/openstack/common/__init__.py
-> 44b6ea3 Import oslo.config configuration file generator
--> cinder/openstack/common/config/__init__.py
-> dd9aa2b Remove unused variables
--> cinder/openstack/common/config/generator.py
-> 5dce17b Use entry points to discover options in libraries
--> tools/config/generate_sample.sh
--> cinder/openstack/common/config/generator.py
-> e8e636c generator: add an EXTRA_LIBRARIES env variable
--> cinder/openstack/common/config/generator.py
-> e3dddd7 generator: use EXTRA_* env vars in the bash script
--> tools/config/generate_sample.sh
--> cinder/openstack/common/config/generator.py
-> 6da13e8 generator: rename EXTRA_MODULES_FILE to RC_FILE
--> tools/config/generate_sample.sh
-> 763eedf Fix DictOpt support in config sample generator
--> cinder/openstack/common/config/generator.py
-> e839886 Config generator fails with lazy messages
--> cinder/openstack/common/config/generator.py
-> 343686b Add check_uptodate to tools/config
--> tools/config/check_uptodate.sh

Oslo version:
-> 0f24d82 Fix migration.db_version when no tables
-> Date: Sat, 22 Feb 2014 00:32:18 +0000

Change-Id: I26a95fe96b08d6340b0fce1b9e2949c8e661a946
Closes-Bug: 1280826
Related-bp: i18n-messages
Re-enable lazy translation

This patch re-enables lazy translation to enable REST API
responses to be translated to the requested locale (I.E. setting
'Accept-Language: zh-CN'.)

This patch also removes the unnecessary manual import of
'cinder.openstack.common.gettextutils _' in Cinder code.  Since _ is
still being imported in the cinder.openstack.common files from Oslo
we still need to set gettexttutils.enable_lazy().  enable_lazy will
be able to be removed once the manual imports of _ have been removed
from Oslo.

implements-bp: i18n-messages
Change-Id: I0b5a35a2cc28d97d12ceccccd58565b487fef428
Merge "Sync latest Oslo config code for i18n"
Merge "Re-enable lazy translation"