Prevent an infinite loop in the migration tool.

git-svn-id: file:///tmp/wdn_thm_drupal/branches/drupal-7.x@169 20a16fea-79d4-4915-8869-1ea9d5ebf173

sites/all/modules/unl/unl_migration.php

@@ -477,8 +477,12 @@ class Unl_Migration_Tool
             while (strpos($parts['path'], '/./') !== FALSE) {
                 $parts['path'] = strtr($parts['path'], array('/./', '/'));
             }
+            $i = 0;
             while (strpos($parts['path'], '/../') !== FALSE) {
                 $parts['path'] = preg_replace('/\\/[^\\/]*\\/\\.\\.\\//', '/', $parts['path']);
+                $parts['path'] = preg_replace('/^\\/\\.\\.\\//', '/', $parts['path']);
+                // Prevent infinite loops if we get some crazy url.
+                if ($i++ > 100) exit;
             }
         }