drupal/core/modules/config/config.module

<?php

/**
 * @file
 * Allows site administrators to modify configuration.
 */

/**
 * Implements hook_help().
 */
function config_help($path, $arg) {
  switch ($path) {
    case 'admin/help#config':
      $output = '';
      $output .= '<h3>' . t('About') . '</h3>';
      $output .= '<p>' . t('The Configuration manager module provides a user interface for importing and exporting configuration changes; i.e., for staging configuration data between multiple instances of this web site. For more information, see the online handbook entry for <a href="!url">Configuration manager module</a>', array(
        '!url' => 'http://drupal.org/documentation/administer/config',
      )) . '</p>';
      return $output;

    case 'admin/config/development/sync':
      $output = '';
      $output .= '<p>' . t('Import configuration that is placed in your staging directory. All changes, deletions, renames, and additions are listed below.') . '</p>';
      return $output;
  }
}

/**
 * Implements hook_permission().
 */
function config_permission() {
  $permissions['synchronize configuration'] = array(
    'title' => t('Synchronize configuration'),
    'restrict access' => TRUE,
  );
  return $permissions;
}

/**
 * Implements hook_menu().
 */
function config_menu() {
  $items['admin/config/development/sync'] = array(
    'title' => 'Synchronize configuration',
    'description' => 'Synchronize configuration changes.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('config_admin_import_form'),
    'access arguments' => array('synchronize configuration'),
    'file' => 'config.admin.inc',
  );
  $items['admin/config/development/sync/import'] = array(
    'title' => 'Import',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );
  return $items;
}