Added support for registration form, script now in iframe.

git-svn-id: https://plugins.svn.wordpress.org/spammers-suck/trunk@753047 b8457f37-d9ea-0310-8a92-e5e31aec5664
Readme update.

git-svn-id: https://plugins.svn.wordpress.org/spammers-suck/trunk@753049 b8457f37-d9ea-0310-8a92-e5e31aec5664