added new screenshot-9.png

git-svn-id: https://plugins.svn.wordpress.org/wp-photo-gallery/trunk@819062 b8457f37-d9ea-0310-8a92-e5e31aec5664
readme.txt changes

git-svn-id: https://plugins.svn.wordpress.org/wp-photo-gallery/trunk@819063 b8457f37-d9ea-0310-8a92-e5e31aec5664