update compatibility

git-svn-id: http://plugins.svn.wordpress.org/google-calendar-events@771109 b8457f37-d9ea-0310-8a92-e5e31aec5664
fix typo

git-svn-id: http://plugins.svn.wordpress.org/google-calendar-events@771110 b8457f37-d9ea-0310-8a92-e5e31aec5664