Add another rule to prevent spam.

the word 'porn' has been turning up a lot lately.

data/spamRules.php

@@ -255,6 +255,11 @@ $rules['text'][] = function($spam) {
         return true;
     }
 
+    if (substr_count($spam, 'porn') > 0) {
+        // No porn
+        return true;
+    }
+
     if (strpos(strtolower($spam), 'cialis') !== false
         || strpos(strtolower($spam), '<a href=') !== false
         || strpos(strtolower($spam), 'bitcoin') !== false