code: function ensureLogsRotated(stats){
      // TODO: other writes should wait until this is done
      var today = new Date(),
          modifiedDate = new Date(stats.mtime),
          archivedFileName;
  
      if(!_logDatesMatch(today, modifiedDate)){
          archivedFileName = _createRotatedLogName(this.config.path, modifiedDate);
          console.log('Log file modified previous to today, archiving to: ' + archivedFileName);
  
          return fs.renameAsync(this.config.path, archivedFileName)
              .bind(this)
              .then(this.createEmptyFile);
      }
  }
docs: Method will look at the stats of a file and if it was modified on a date that was not today then it will
  rename it to it's modfied date so we can start fresh daily.
  @param stats Stats of a file
  @returns {string} Status of rotation ('datematches' - do nothing, 'logrotated' - change detected rename file)