updated readme

git-svn-id: https://plugins.svn.wordpress.org/zedity/trunk@783566 b8457f37-d9ea-0310-8a92-e5e31aec5664
Released version 1.4.0

git-svn-id: https://plugins.svn.wordpress.org/zedity/trunk@783953 b8457f37-d9ea-0310-8a92-e5e31aec5664