Merged 1.3 to master.

git-svn-id: http://plugins.svn.wordpress.org/delightful-downloads/trunk@821444 b8457f37-d9ea-0310-8a92-e5e31aec5664
Updated readme and lang files.

git-svn-id: http://plugins.svn.wordpress.org/delightful-downloads/trunk@821445 b8457f37-d9ea-0310-8a92-e5e31aec5664
Added upgrade notices to readme.

git-svn-id: http://plugins.svn.wordpress.org/delightful-downloads/trunk@821514 b8457f37-d9ea-0310-8a92-e5e31aec5664
Version 1.3.1. Fixed download bug.