code: function Transfer(transfer, options) {
      this.main = transfer;
      this.$main = $(this.main);
  
      var defaultOption = {
          theme: window.bizui.theme,
          customClass: '',
          dataSource: [],
          keyMap: {
              id: 'id',
              title: 'title',
              chosen: 'chosen'
          },
          titles: ['请选择', '已选择'],
          noContent: '请新增选项'
      };
      this.options = $.extend(defaultOption, options || {});
      this.init(this.options);
  }
docs: Transfer
  @class
  @param {HTMLElement} transfer              目标元素
  @param {Object}      [options]             参数
  @param {String}      [options.customClass] 自定义 class
  @param {Array}       [options.dataSource]  数据
  @param {Object}      [options.keyMap]      数据字段，默认 {id: 'id', title: 'title', chosen: 'chosen'}
  @param {Array}       [options.titles]      标题
  @param {String}      [options.noContent]   无数据提示，不转义
  @param {Function}    [options.onChange]    移动数据回调，onChange(Array data, Event e)
  @param {String}      [options.theme]       主题