merge r2020 from branch 17 to trunk

- invalid html in page banner on admin page might interfere with actual page

git-svn-id: http://piwigo.org/svn/trunk@2021 68402e56-0260-453c-a942-63ccdbb3a9ee

admin/configuration.php

@@ -217,8 +217,8 @@ switch ($page['section'])
       array(
         'GALLERY_LOCKED_YES'=>$lock_yes,
         'GALLERY_LOCKED_NO'=>$lock_no,
-        'CONF_GALLERY_TITLE' => $conf['gallery_title'],
-        'CONF_PAGE_BANNER' => $conf['page_banner'],
+        'CONF_GALLERY_TITLE' => htmlspecialchars($conf['gallery_title']),
+        'CONF_PAGE_BANNER' => htmlspecialchars($conf['page_banner']),
         'CONF_GALLERY_URL' => $conf['gallery_url'],
         ));