Updated trunk to 0.3; released version 0.3

git-svn-id: https://plugins.svn.wordpress.org/is-user-premium/trunk@1015289 b8457f37-d9ea-0310-8a92-e5e31aec5664
Added screenshots to 0.3, readme update

git-svn-id: https://plugins.svn.wordpress.org/is-user-premium/trunk@1015299 b8457f37-d9ea-0310-8a92-e5e31aec5664