Small update to plugin readme.txt file.

git-svn-id: https://plugins.svn.wordpress.org/wp-symposium-pro/trunk@903654 b8457f37-d9ea-0310-8a92-e5e31aec5664
Small update to plugin readme.txt file.

git-svn-id: https://plugins.svn.wordpress.org/wp-symposium-pro/trunk@903656 b8457f37-d9ea-0310-8a92-e5e31aec5664