[IMP] website_sale_digital: add message when no record

Proper message should be displayed when no records in
attachments kanban view when we click on 'File' stat
button on product form view.

addons/website_sale_digital/models/product.py

@@ -27,6 +27,10 @@ class ProductTemplate(models.Model):
             'view_mode': 'kanban,form',
             'view_type': 'form',
             'context': "{'default_res_model': '%s','default_res_id': %d, 'default_product_downloadable': True}" % (self._name, self.id),
+            'help': """
+                <p class="oe_view_nocontent_create">Click on create to add attachments for this digital product.</p>
+                <p>The attached files are the ones that will be purchased and sent to the customer.</p>
+                """,
         }
 
 
@@ -56,4 +60,8 @@ class Product(models.Model):
             'view_mode': 'kanban,form',
             'view_type': 'form',
             'context': "{'default_res_model': '%s','default_res_id': %d, 'default_product_downloadable': True}" % (self._name, self.id),
+            'help': """
+                <p class="oe_view_nocontent_create">Click on create to add attachments for this digital product.</p>
+                <p>The attached files are the ones that will be purchased and sent to the customer.</p>
+                """,
         }