Fix customer backend forms , fix site\index

backend create\update customer forms must display the same as the frontend
forms

site\index action should be friendly and related to this app

backend/controllers/CustomerController.php

@@ -79,6 +79,8 @@ class CustomerController extends \backend\controllers\BackendController
             throw new NotFoundHttpException('The requested page does not exist.');
         }
         
+        $model->birthdate= isset($model->birthdate ) ? Yii::$app->formatter->asDate($model->birthdate) :'';
+        
 
         if ($model->load(Yii::$app->request->post()) && $model->save()) {
             return $this->redirect(['view', 'id' => $model->id_customer]);