code: function(options) {
      this.transformations = options.transformations || [];
      this.rootUrl = options.baseUrl;
      this.baseUrl = options.baseUrl;
      this.user = options.user || options.publicKey;
      this.publicKey = options.publicKey;
      this.privateKey = options.privateKey;
      this.imageIdentifier = options.imageIdentifier;
      this.extension = options.extension;
      this.queryString = options.queryString;
      this.path = options.path || '';
  
      this.baseUrl += [
          '/users', this.user,
          'images', this.imageIdentifier
      ].join('/');
  }
docs: ImageUrl constructor
  
  @param {Object} options