fix update.php path

Easy fix =)

Hmm, two questions:

1. http://mysite.com/update.php does seem to redirect to http://mysite.com/core/update.php. Do we need to make this change?
2. If we do need to make the change, then shouldn't we change it in other places as well?

Re: #2 -- I don't understand what you mean? This doesn't apply to D7 at all so of course it has to be for D8.

Edit: I'm an idiot, and you're right, I had 7.x checked out when I grepped. Carry on. :P

So, yeah, all the other instances are actually fixed already:

[milankovitch:drupal | Fri 06:43:26] $ grep -rn -B 1 "/update.php" *
core/includes/install.core.inc-1325-  drupal_set_title(st('Drupal already installed'));
core/includes/install.core.inc:1326:  return st('<ul><li>To start over, you must empty your existing database.</li><li>To install to a different database, edit the appropriate <em>settings.php</em> file in the <em>sites</em> folder.</li><li>To upgrade an existing installation, proceed to the <a href="@base-url/update.php">update script</a>.</li><li>View your <a href="@base-url">existing site</a>.</li></ul>', array('@base-url' => $base_url));
--
core/modules/simpletest/tests/upgrade/upgrade.test-245-  protected function performUpgrade($register_errors = TRUE) {
core/modules/simpletest/tests/upgrade/upgrade.test:246:    $update_url = $GLOBALS['base_url'] . '/core/update.php';
--
core/modules/system/system.install-376-          $requirements['update']['value'] = $t('Out of date');
core/modules/system/system.install:377:          $requirements['update']['description'] = $t('Some modules have database schema updates to install. You should run the <a href="@update">database update script</a> immediately.', array('@update' => base_path() . 'core/update.php'));
--
core/modules/system/system.module-110-        if (update_manager_access()) {
core/modules/system/system.module:111:          $output .= '<p>' . t('Regularly review and install <a href="@updates">available updates</a> to maintain a secure and current site. Always run the <a href="@update-php">update script</a> each time a module is updated.', array('@update-php' => $base_url . '/core/update.php', '@updates' => url('admin/reports/updates'))) . '</p>';
--
core/modules/system/system.module-113-        else {
core/modules/system/system.module:114:          $output .= '<p>' . t('Regularly review <a href="@updates">available updates</a> to maintain a secure and current site. Always run the <a href="@update-php">update script</a> each time a module is updated.', array('@update-php' => $base_url . '/core/update.php', '@updates' => url('admin/reports/updates'))) . '</p>';
--
core/modules/system/system.module-117-      else {
core/modules/system/system.module:118:        $output .= '<p>' . t('Regularly review available updates to maintain a secure and current site. Always run the <a href="@update-php">update script</a> each time a module is updated. Enable the Update manager module to update and install modules and themes.', array('@update-php' => $base_url . '/core/update.php')) . '</p>';
--
core/modules/system/system.test-2122-    parent::setUp('update_script_test');
core/modules/system/system.test:2123:    $this->update_url = $GLOBALS['base_url'] . '/core/update.php';
--
core/modules/update/update.authorize.inc-213-  $results['tasks'][] = t('Your modules have been downloaded and updated.');
core/modules/update/update.authorize.inc:214:  $results['tasks'][] = t('<a href="@update">Run database updates</a>', array('@update' => base_path() . 'core/update.php'));
--
core/modules/update/update.module-664-    file_exists("$directory/$project/index.php")
core/modules/update/update.module:665:    && file_exists("$directory/$project/core/update.php")
--
core/update.php-6- *
core/update.php:7: * Point your browser to "http://www.example.com/core/update.php" and follow the
--
core/update.php-148-  // NOTE: we can't use l() here because the URL would point to
core/update.php:149:  // 'core/update.php?q=admin'.
--
core/update.php-395-  // Redirect to the update information page if all requirements were met.
core/update.php:396:  install_goto('core/update.php?op=info');
--
core/UPGRADE.txt-97-
core/UPGRADE.txt:98:6. Run update.php by visiting http://www.example.com/core/update.php (replace
--
core/UPGRADE.txt-204-
core/UPGRADE.txt:205:14. Run update.php by visiting http://www.example.com/core/update.php (replace

Committed to 8.x. Good catch. Thanks.