message: drake: show the duration of the runs
diff: @@ -2127,7 +2127,12 @@ class Builder:
  if dst.touch(res):
  print('Adjust mtime of %s' % dst)
  if execute:
  + import time, datetime
  + self.__start_time = time.time()
  self._execute(depfile_builder)
  + self.__end_time = time.time()
  + d = round(self.__end_time - self.__start_time)
  + print('Finished {} ({})'.format(node, datetime.timedelta(seconds=d)))
  else:
  self.__executed = True
  logger.log('drake.Builder',
  