Version 1.6.4

git-svn-id: https://plugins.svn.wordpress.org/fpw-category-thumbnails/trunk@1001913 b8457f37-d9ea-0310-8a92-e5e31aec5664
Version 1.6.4 .pot file

git-svn-id: https://plugins.svn.wordpress.org/fpw-category-thumbnails/trunk@1001915 b8457f37-d9ea-0310-8a92-e5e31aec5664