Refactored log_timing and added total_seconds_last_epoch to monitors
reverted timing.py and set timing() to log_timing(logging.DEBUG)
Merge remote-tracking branch 'upstream/master' into monitoring_time
added line for PEP8
Merge remote-tracking branch 'upstream/master' into monitoring_time
Merge pull request #568 from bouthilx/monitoring_time

Refactored log_timing and added total_seconds_last_epoch to monitors #564