3.5.7 - move extend file to uploads dir

git-svn-id: https://plugins.svn.wordpress.org/wp-noexternallinks/trunk@1041052 b8457f37-d9ea-0310-8a92-e5e31aec5664
update readme.txt

git-svn-id: https://plugins.svn.wordpress.org/wp-noexternallinks/trunk@1041054 b8457f37-d9ea-0310-8a92-e5e31aec5664