Changed the version to 2.0.3.1.

git-svn-id: https://plugins.svn.wordpress.org/amazon-auto-links/trunk@832004 b8457f37-d9ea-0310-8a92-e5e31aec5664
Marked 2.0.3.1 as stable.

git-svn-id: https://plugins.svn.wordpress.org/amazon-auto-links/trunk@832006 b8457f37-d9ea-0310-8a92-e5e31aec5664