update upgrade note for 2.4

UPGRADE-2.4.md

@@ -7,13 +7,18 @@ You will need to follow the dependencies upgrade instructions.
 
 ## Datagrid builders
 
-If you have implemented a custom datagrid builder, you must adapt the signature
-of its `addFilter` method to match the one in `DatagridBuilderInterface` again.
+If you have implemented a custom datagrid builder, you must adapt the signature of its `addFilter` method to match the one in `DatagridBuilderInterface` again.
 
 ## sonata_type_model_autocomplete
-CSS class ``sonata-autocomplete-dropdown-item`` is not automatically added to
-dropdown autocomplete item in ``sonata_type_model_autocomplete``, use option
-``dropdown_item_css_class`` to set the CSS class of dropdown item.
+CSS class ``sonata-autocomplete-dropdown-item`` is not automatically added to dropdown autocomplete item in ``sonata_type_model_autocomplete``, use option ``dropdown_item_css_class`` to set the CSS class of dropdown item.
 
 ## Standard Layout
 ``sonata_wrapper`` block was moved and is now inside the ``.wrapper`` div of admin lte theme.
+
+## ErrorElement
+
+The inline validation has been migrating to CoreBundle. Just rename ``Sonata\AdminBundle\Validator\ErrorElement`` to ``Sonata\CoreBundle\Validator\ErrorElement``
+
+## AdminLTE 2
+
+AdminLTE version 2 has been integrated, this should work out of the box if you havn't change templates. If not you can review the upgrade guide here : [http://almsaeedstudio.com/themes/AdminLTE/documentation/index.html#upgrade](http://almsaeedstudio.com/themes/AdminLTE/documentation/index.html#upgrade)