Commit version 1.5.1 again

git-svn-id: https://plugins.svn.wordpress.org/humancaptcha/trunk@757200 b8457f37-d9ea-0310-8a92-e5e31aec5664
Commit version 1.5.1 again

git-svn-id: https://plugins.svn.wordpress.org/humancaptcha/trunk@757203 b8457f37-d9ea-0310-8a92-e5e31aec5664