Updated for WP 3.9

git-svn-id: https://plugins.svn.wordpress.org/flynsarmy-iframe-shortcode/trunk@905138 b8457f37-d9ea-0310-8a92-e5e31aec5664
Updated readme

git-svn-id: https://plugins.svn.wordpress.org/flynsarmy-iframe-shortcode/trunk@905139 b8457f37-d9ea-0310-8a92-e5e31aec5664