update readme.txt

git-svn-id: https://plugins.svn.wordpress.org/wp-clean-up-optimizer/trunk@1023711 b8457f37-d9ea-0310-8a92-e5e31aec5664
update text


git-svn-id: https://plugins.svn.wordpress.org/wp-clean-up-optimizer/trunk@1023714 b8457f37-d9ea-0310-8a92-e5e31aec5664