code: function uploadMissing(missing, request, host, log, fn) {
    var batch = new Batch();
  
    missing.forEach(function(file) {
      batch.push(uploadFile(file, request, host));
    });
  
    batch.on('progress', function() {
      log('.');
    });
  
    batch.end(function(err, res) {
      log(' done\n');
      fn(err, res);
    });
  }
docs: Upload the missing files to the build server
  
  @param {Array} missing
  @param {Request} request
  @param {String} host
  @param {Function} fn