Sync latest oslo-incubator log for debug fixes

Sync latest oslo-incubator log for debug fixes

This patch pulls in the changes in openstack/common/log.py that
fix the problems that popped up after we removed _() from
around LOG.debug messages.  The change in log ensures that any
text that is not of six.text_type is converted to six.text_type.

Current HEAD in OSLO:
---------------------
commit 759bd8791ec6a4b0e89f649a4179d177530e7536
Merge: 71d072f 631f880
Author: Jenkins <jenkins@review.openstack.org>
Date:   Wed Aug 13 13:37:27 2014 +0000

Merge "Set keystonemiddleware and routes.middleware to log on WARN level"
---------------------

Additional changes being merged (newest to oldest):
---------------------
759bd879 -
Merge "Set keystonemiddleware and routes.middleware to log on WARN level
71d072f1 -
Merge "Except socket.error if syslog isn't running"
37c00918 -
Add unicode coercion of logged messages to ContextFormatter
66144135 -
Correct coercion of logged message to unicode
1188d88a -
Except socket.error if syslog isn't running
ac995bec -
Fix E126 pep8 errors

Note that this change required an update to config.sample due to change
759bd879 -  Merge "Set keystonemiddleware and routes.middleware to log
on WARN level"

Change-Id: I4b849981c65300b327076d68fbf8601d46ec61f0
Closes-Bug: 1348244