lib/syncmanager.js
function(callback) {
    async.series([
      this.downloadPackageRootObjects.bind(this),
      this.downloadPackageVersions.bind(this)
    ], function(err) {
      return callback && callback(err);
    });
  }
function(callback) {
    async.series([
      this.downloadPackageRootObjects.bind(this),
      this.downloadPackageVersions.bind(this)
    ], function(err) {
      return callback && callback(err);
    });
  }
function ( callback ) { async . series ( [ this . downloadPackageRootObjects . bind ( this ) , this . downloadPackageVersions . bind ( this ) ] , function ( err ) { return callback && callback ( err ) ; } ) ; }
Download all the package root objects, package version objects,
and tarballs.

@param {Function} callback invoke when done.
Download all the package root objects package version objects and tarballs .