Replaced screenshot-1.PNG

git-svn-id: https://plugins.svn.wordpress.org/after-post-manager/trunk@1006026 b8457f37-d9ea-0310-8a92-e5e31aec5664
Changed screenshot-1 extension.

git-svn-id: https://plugins.svn.wordpress.org/after-post-manager/trunk@1006027 b8457f37-d9ea-0310-8a92-e5e31aec5664