code: function resolvePackageId(id) {
          each(
              packagesIndex,
              function (packageConf) {
                  var name = packageConf.name;
                  if (name === id) {
                      id = name + '/' + packageConf.main;
                      return false;
                  }
              }
          );
  
          return id;
      }
docs: 对id进行package解析
  如果是package，则附加主模块id
  
  @inner
  @param {string} id 模块id
  @return {string} 解析后的id