docs: function writeBonusFile(filename, header, content, sysLogger) {
      var bonusFile;
      bonusFile = fs.createWriteStream(filename);
      bonusFile.on('error', function(err) {
          sysLogger.log('Error while saving bonus file: ' + filename, 'error');
          sysLogger.log(err, 'error');
      });
      bonusFile.on('close', function() {
          sysLogger.log('Bonus file saved: ' + filename);
      });
      bonusFile.write(header.join(',') + '\n');
      bonusFile.write(content);
      bonusFile.end();
  }