Better support for Use tag (#10)

Author: PhenX

src/Svg/Tag/UseTag.php

@@ -2,7 +2,7 @@
 /**
  * @package php-svg-lib
  * @link    http://github.com/PhenX/php-svg-lib
- * @author  Fabien Ménager <[email protected]>
+ * @author  Fabien M�nager <[email protected]>
  * @license http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
  */
 
@@ -41,6 +41,10 @@ protected function before($attributes)
         $link = $attributes["xlink:href"];
         $this->reference = $document->getDef($link);
 
+        if ($this->reference) {
+            $this->reference->before($attributes);
+        }
+
         $surface = $document->getSurface();
         $surface->save();
 
@@ -50,6 +54,10 @@ protected function before($attributes)
     protected function after() {
         parent::after();
 
+        if ($this->reference) {
+            $this->reference->after();
+        }
+
         $this->getDocument()->getSurface()->restore();
     }