oauthdesktop/logger.py should have configurable log level

[Roman Yepishev]

Binary package hint: ubuntuone-client

Currently log_level is set to INFO in oauthdesktop/logger.py:

LOGFILENAME = os.path.join(LOGFOLDER, 'oauth-login.log')

# Only log this level and above
LOG_LEVEL = logging.INFO

root_formatter = logging.Formatter(
    fmt="%(asctime)s:%(msecs)s %(name)s %(message)s")
root_handler = RotatingFileHandler(LOGFILENAME, maxBytes=1048576,
                                   backupCount=1)
root_handler.setLevel(LOG_LEVEL)

This makes it rather hard to debug oauthdesktop-related issues since debug statements are there but they cannot be turned on easily.

oauth.conf should be created and read by oauthdesktop that will contain at least
[__main__]
log_level = DEBUG

Additionally the code in logger.py should actually use the root_formatter defined. It looks like this statement got removed in some build.