WP 3.0 compatibility fixes

git-svn-id: https://plugins.svn.wordpress.org/recently-edited-content-widget/trunk@861804 b8457f37-d9ea-0310-8a92-e5e31aec5664
Added screenshots

git-svn-id: https://plugins.svn.wordpress.org/recently-edited-content-widget/trunk@861908 b8457f37-d9ea-0310-8a92-e5e31aec5664