Fixed the do_xss_clean() method so that if file_get_contents returns FALSE, then we return FALSE...

Previously, if it did NOT return FALSE we returned FALSE and that is simply idiotic.
diff --git a/system/libraries/Upload.php b/system/libraries/Upload.php
index dc3fd4a..9d2bae2 100644
--- a/system/libraries/Upload.php
+++ b/system/libraries/Upload.php
@@ -709,7 +709,7 @@
 			return FALSE;

 		}

 

-		if (($data = @file_get_contents($file)) !== FALSE)

+		if (($data = @file_get_contents($file)) === FALSE)

 		{

 			return FALSE;

 		}