Tagging readme-update as release


git-svn-id: https://plugins.svn.wordpress.org/pdf-thumbnails/trunk@894220 b8457f37-d9ea-0310-8a92-e5e31aec5664
Updated readme.. again


git-svn-id: https://plugins.svn.wordpress.org/pdf-thumbnails/trunk@894221 b8457f37-d9ea-0310-8a92-e5e31aec5664