update trunk stable tag in readme

git-svn-id: https://plugins.svn.wordpress.org/quiz-tool-lite/trunk@1036761 b8457f37-d9ea-0310-8a92-e5e31aec5664
try again..

git-svn-id: https://plugins.svn.wordpress.org/quiz-tool-lite/trunk@1036768 b8457f37-d9ea-0310-8a92-e5e31aec5664