Urgent security release of e107 CMS

An urgent security release of e107 has been made available. This is a mandatory update for those running the popular content management system. A full changelog identifying the fixes can be found here: http://e107.org/svn_changelog.php?version=0.7.21

Please ensure you upgrade immediately. You can do so by downloading the latest version from: http://www.e107.org/news.php?item.865.1