added style.css

git-svn-id: https://plugins.svn.wordpress.org/advance-widget-pack/trunk@977731 b8457f37-d9ea-0310-8a92-e5e31aec5664
added screenshots

git-svn-id: https://plugins.svn.wordpress.org/advance-widget-pack/trunk@977734 b8457f37-d9ea-0310-8a92-e5e31aec5664