upadte readme.txt

git-svn-id: https://plugins.svn.wordpress.org/photos-box/trunk@1038620 b8457f37-d9ea-0310-8a92-e5e31aec5664
update photos-box.php

git-svn-id: https://plugins.svn.wordpress.org/photos-box/trunk@1038622 b8457f37-d9ea-0310-8a92-e5e31aec5664