changed order of preloading components and extensions

load extensions before preloading components to have aliases set for
extensions like debug module.

framework/yii/base/Application.php

@@ -204,8 +204,8 @@ abstract class Application extends Module
 	 */
 	public function init()
 	{
-		parent::init();
 		$this->initExtensions($this->extensions);
+		parent::init();
 	}
 
 	/**