- new feature : RSS notification feed. Feed generator is an external tool

(FeedCreator class v1.7.2). New file feed.php

- new database field : comments.validation_date (datetime). This field is
  required for notification feed.

- new database field : users.feed_id (varchar(50)). users.feed_id is an
  alias of users.id but is much more complicated to find (50 characters,
  figures or letters, case sensitive) : the purpose is to keep it secret (as
  far as possible).

- new database field : users.last_feed_check (datetime)

- new database field : users.registration_date (datetime)

- bug fixed : no need to add the (unavailable) session id to install.php in
  the installation form.

- modified database field : images.date_available become more precise (date
  to datetime). This precision is needed for notification feed.

- new index : comments_i1 (validation_date). Might be useful for feed
  queries.

- new index : comments_i2 (image_id). Useful each time you want to have
  informations about an element and its associated comments.

- version 9.11 of mysqldump outputs database field names and table names
  with backquote "`" (didn't find how to take them off)


git-svn-id: http://piwigo.org/svn/trunk@801 68402e56-0260-453c-a942-63ccdbb3a9ee

admin/picture_modify.php

@@ -180,7 +180,8 @@ $template->assign_vars(array(
   'NAME_IMG'=>isset($_POST['name'])?$_POST['name']:@$row['name'],
   'SIZE_IMG'=>@$row['width'].' * '.@$row['height'],
   'FILESIZE_IMG'=>@$row['filesize'].' KB',
-  'REGISTRATION_DATE_IMG'=> format_date($row['date_available']),
+  'REGISTRATION_DATE_IMG'
+  => format_date($row['date_available'], 'mysql_datetime', true),
   'AUTHOR_IMG'=>isset($_POST['author'])?$_POST['author']:@$row['author'],
   'CREATION_DATE_IMG'=>$date,
   'KEYWORDS_IMG'=>isset($_POST['keywords'])?$_POST['keywords']:@$row['keywords'],