Added more info to readme.txt

git-svn-id: https://plugins.svn.wordpress.org/wp-symposium-pro/trunk@905943 b8457f37-d9ea-0310-8a92-e5e31aec5664
Added more info to readme.txt

git-svn-id: https://plugins.svn.wordpress.org/wp-symposium-pro/trunk@905946 b8457f37-d9ea-0310-8a92-e5e31aec5664
Added more info to readme.txt

git-svn-id: https://plugins.svn.wordpress.org/wp-symposium-pro/trunk@905947 b8457f37-d9ea-0310-8a92-e5e31aec5664