Update readme.txt for code blocks

git-svn-id: https://plugins.svn.wordpress.org/twitter-reaper/trunk@1045263 b8457f37-d9ea-0310-8a92-e5e31aec5664
Update readme.txt for code blocks

git-svn-id: https://plugins.svn.wordpress.org/twitter-reaper/trunk@1045266 b8457f37-d9ea-0310-8a92-e5e31aec5664