4.0 readme update

git-svn-id: https://plugins.svn.wordpress.org/advanced-dates/trunk@980895 b8457f37-d9ea-0310-8a92-e5e31aec5664
4.0 readme update

git-svn-id: https://plugins.svn.wordpress.org/advanced-dates/trunk@980897 b8457f37-d9ea-0310-8a92-e5e31aec5664