code: function(cb) {
              log.log('git pull origin ' + branch + ' ' + repoDir);
              git(repoDir, ['pull', 'origin', branch], function(err, stdout, stderr) {
                  if (err) {
                      log.error('Unable to pull at ' + repoDir + ':', err.msg);
                  }
                  cb(err, {pull: {stdout: stdout, stderr: stderr}})
              });
          }
docs: Pull.