updated readme

git-svn-id: https://plugins.svn.wordpress.org/simplerestrict/trunk@1028569 b8457f37-d9ea-0310-8a92-e5e31aec5664
updated readme format

git-svn-id: https://plugins.svn.wordpress.org/simplerestrict/trunk@1028573 b8457f37-d9ea-0310-8a92-e5e31aec5664