When using debug level the log files tends to fill up quickly.
Add support for log rotation using lumberjack, simple and easy to use
log rotation module.
Signed-off-by: Shahar Klein <sklein@nvidia.com>
This changes adds logging message:debug and error. fmt.Errorf() is
wrapped by logging.Errorf() hence all error message is also put to
log file. logging.Debugf() is called at almost function call, so
we could track the code by logging message.
