readme update

git-svn-id: https://plugins.svn.wordpress.org/wp-shop-original/trunk@994621 b8457f37-d9ea-0310-8a92-e5e31aec5664
readme.txt update

git-svn-id: https://plugins.svn.wordpress.org/wp-shop-original/trunk@994625 b8457f37-d9ea-0310-8a92-e5e31aec5664