add thumbnail size

git-svn-id: https://plugins.svn.wordpress.org/parks-parker-post-formats/trunk@853353 b8457f37-d9ea-0310-8a92-e5e31aec5664
bump to v0.3

git-svn-id: https://plugins.svn.wordpress.org/parks-parker-post-formats/trunk@853354 b8457f37-d9ea-0310-8a92-e5e31aec5664