Remove duplicate strtolower calls and don't use it in multibyte comparisons

Closes #19

data/spamRules.php

@@ -321,8 +321,9 @@ $rules['url'][] = function($spam) {
 };
 
 $rules['text'][] = function($spam) {
-    if (strpos(strtolower($spam), '[link') !== false
-        || strpos(strtolower($spam), '[url') !== false) {
+	$spamLower = strtolower($spam);
+    if (strpos($spamLower, '[link') !== false
+        || strpos($spamLower, '[url') !== false) {
         // Sorry bbcode spammers
         return true;
     }
@@ -364,42 +365,42 @@ $rules['text'][] = function($spam) {
         return true;
     }
 
-    if (strpos(strtolower($spam), 'cialis') !== false
-        || strpos(strtolower($spam), '?>') !== false
-        || strpos(strtolower($spam), '<a href=') !== false
-        || strpos(strtolower($spam), 'bitcoin') !== false
-        || strpos(strtolower($spam), 'augmentin') !== false
-        || strpos(strtolower($spam), 'xfather123') !== false
-        || strpos(strtolower($spam), 'viagra') !== false
-        || strpos(strtolower($spam), '?>') !== false
-        || strpos(strtolower($spam), 'levitra') !== false
-        || strpos(strtolower($spam), 'linkspirit.net') !== false
-        || strpos(strtolower($spam), 'lowest-rate-loans') !== false
-        || strpos(strtolower($spam), 'topthesis.com') !== false
-        || strpos(strtolower($spam), 'weddingdresses') !== false
-        || strpos(strtolower($spam), 'muscle relaxants') !== false
-        || strpos(strtolower($spam), 'acomplia') !== false
-        || strpos(strtolower($spam), 'zithromax') !== false
-        || strpos(strtolower($spam), 'pavtube') !== false
-        || strpos(strtolower($spam), 'azithromycin') !== false
-        || strpos(strtolower($spam), 'calfskin leather') !== false
-        || strpos(strtolower($spam), 'xanax') !== false
-        || strpos(strtolower($spam), 'xenical') !== false
-        || strpos(strtolower($spam), 'alprazolam') !== false
-        || strpos(strtolower($spam), 'stop hack the program!!!') !== false
-        || strpos(strtolower($spam), 'cheapmac-wholesale.com') !== false
-        || strpos(strtolower($spam), 'uggbootssale') !== false
-        || strpos(strtolower($spam), 'michael kors') !== false
-        || strpos(strtolower($spam), 'cheap pills') !== false
-        || strpos(strtolower($spam), 'tramadol') !== false
-        || strpos(strtolower($spam), 'online pharmacy') !== false
-        || strpos(strtolower($spam), 'free-blog-site.com') !== false
-        || strpos(strtolower($spam), 'samsung1080phdtv.net') !== false
-        || strpos(strtolower($spam), 'ccleungwebdesign.com') !== false
-        || strpos(strtolower($spam), 'freemoviesonlinetv.net') !== false
-        || strpos(strtolower($spam), 'onlovetech') !== false
-        || strpos(strtolower($spam), 'b4yporn.com') !== false
-        || strpos(strtolower($spam), 'forex') !== false
+    if (strpos($spamLower, 'cialis') !== false
+        || strpos($spamLower, '?>') !== false
+        || strpos($spamLower, '<a href=') !== false
+        || strpos($spamLower, 'bitcoin') !== false
+        || strpos($spamLower, 'augmentin') !== false
+        || strpos($spamLower, 'xfather123') !== false
+        || strpos($spamLower, 'viagra') !== false
+        || strpos($spam, '?') !== false
+        || strpos($spamLower, 'levitra') !== false
+        || strpos($spamLower, 'linkspirit.net') !== false
+        || strpos($spamLower, 'lowest-rate-loans') !== false
+        || strpos($spamLower, 'topthesis.com') !== false
+        || strpos($spamLower, 'weddingdresses') !== false
+        || strpos($spamLower, 'muscle relaxants') !== false
+        || strpos($spamLower, 'acomplia') !== false
+        || strpos($spamLower, 'zithromax') !== false
+        || strpos($spamLower, 'pavtube') !== false
+        || strpos($spamLower, 'azithromycin') !== false
+        || strpos($spamLower, 'calfskin leather') !== false
+        || strpos($spamLower, 'xanax') !== false
+        || strpos($spamLower, 'xenical') !== false
+        || strpos($spamLower, 'alprazolam') !== false
+        || strpos($spamLower, 'stop hack the program!!!') !== false
+        || strpos($spamLower, 'cheapmac-wholesale.com') !== false
+        || strpos($spamLower, 'uggbootssale') !== false
+        || strpos($spamLower, 'michael kors') !== false
+        || strpos($spamLower, 'cheap pills') !== false
+        || strpos($spamLower, 'tramadol') !== false
+        || strpos($spamLower, 'online pharmacy') !== false
+        || strpos($spamLower, 'free-blog-site.com') !== false
+        || strpos($spamLower, 'samsung1080phdtv.net') !== false
+        || strpos($spamLower, 'ccleungwebdesign.com') !== false
+        || strpos($spamLower, 'freemoviesonlinetv.net') !== false
+        || strpos($spamLower, 'onlovetech') !== false
+        || strpos($spamLower, 'b4yporn.com') !== false
+        || strpos($spamLower, 'forex') !== false
         || strpos($spam, 'Ñ€Ð') !== false
         || strpos($spam, '�') !== false) {
         // Spam