code: function md5Salt(value, salt = 'abcdefghijklmnopqrstuvwxyz1234567890') {
      let ins = crypto.createHash('md5');
      value = value + salt.slice(value.length % salt.length, salt.length);
      ins.update(value);    
      return ins.digest('hex');
  }
docs: Calculate the value of MD5 hash value, including simple salt
  
  @param {string} value
  @param {string} [salt='abcdefghijklmnopqrstuvwxyz1234567890']
  @returns