Replace Google reCAPTCHA API's domain (#507)

This makes it accessible in mainland China.

Sources:
google/recaptcha#227
https://developers.google.com/recaptcha/docs/faq#can-i-use-recaptcha-globally
https://meta.stackoverflow.com/questions/402339/please-change-the-recaptcha-link-to-ensure-the-site-is-accessible-in-china

Co-Authored-By: Fredrick Brennan <[email protected]>

post.php

@@ -444,7 +444,7 @@ if (isset($_POST['delete'])) {
 				error($config['error']['bot']);	
 
 			// Check what reCAPTCHA has to say...
-			$resp = json_decode(file_get_contents(sprintf('https://www.google.com/recaptcha/api/siteverify?secret=%s&response=%s&remoteip=%s',
+			$resp = json_decode(file_get_contents(sprintf('https://www.recaptcha.net/recaptcha/api/siteverify?secret=%s&response=%s&remoteip=%s',
 				$config['recaptcha_private'],
 				urlencode($_POST['g-recaptcha-response']),
 				$_SERVER['REMOTE_ADDR'])), true);

templates/header.html

@@ -21,7 +21,7 @@
 			<script type="text/javascript" src="/js/mod/mod_snippets.js"></script>
 			{% endif %}
 		{% endif %}
-		{% if config.recaptcha %}<script src="//www.google.com/recaptcha/api.js"></script>
+		{% if config.recaptcha %}<script src="//www.recaptcha.net/recaptcha/api.js"></script>
 		<style type="text/css">{% verbatim %}
 			#recaptcha_area {
 				float: none !important;