Fixed bug with signups spam test.

git-svn-id: https://plugins.svn.wordpress.org/cleantalk-spam-protect/trunk@869754 b8457f37-d9ea-0310-8a92-e5e31aec5664
Fixed switching to file_get_contents().

git-svn-id: https://plugins.svn.wordpress.org/cleantalk-spam-protect/trunk@869797 b8457f37-d9ea-0310-8a92-e5e31aec5664