convert isBlacklisted method in public to be able to use library with…

…out email pattern checking

platform/php/MailChecker.php

@@ -31,7 +31,7 @@ private static function validEmail($email) {
         }
     }
 
-    private static function isBlacklisted($email) {
+    public static function isBlacklisted($email) {
         $parts = explode("@", $email);
         $domain = end($parts);