readme update

git-svn-id: https://plugins.svn.wordpress.org/wpsso/trunk@944053 b8457f37-d9ea-0310-8a92-e5e31aec5664
readme and/or setup guide update

git-svn-id: https://plugins.svn.wordpress.org/wpsso/trunk@944055 b8457f37-d9ea-0310-8a92-e5e31aec5664