updated readme.txt

git-svn-id: https://plugins.svn.wordpress.org/image-elevator/trunk@956034 b8457f37-d9ea-0310-8a92-e5e31aec5664
readme.txt

git-svn-id: https://plugins.svn.wordpress.org/image-elevator/trunk@956035 b8457f37-d9ea-0310-8a92-e5e31aec5664