For a long time now, Djblets has provided support for providing a Django

HTTP request to logging statements through a request= keyword argument.

This has generally worked, but some users have encountered somewhat

sporadic problems with this. This turns out to be related to our move to

using logging.exception() instead of logging.error(..., exc_info=True)

in places.
logging.exception() was missing support for keyword arguments on

Python 2.6.x, 2.7.0-2.7.5, 3.0.x, and 3.1.x. 2.7.6+ and 3.2.x+ fixed

this, but anyone running an older version would not be able to use

request= or even extra=.
Along with this, any custom loggers from logging.getLogger('...')

would fail to support request=, because we only patched up the root

logger.
This change fixes these issues by patching any versions of

logging.exception() that are missing keyword argument support, and

wrapping logging.Logger so all loggers will benefit from request=.

Unit tests passed on Python 2.6 and 2.7. Previously, these new tests

failed on 2.6.
Sanity-checked that exception logs (and others) worked with request=.