UPGRADE FROM 2.2 to 2.3
=======================

### Dependencies

You'll need to follow the dependencies upgrade instructions.

### Templates

 - `standard_layout.html.twig` has been updated (refactored layout accordingly to the theme). Some blocks have been moved, and the sonata_side_nav twig block became the main menu.
 - Admin's sidemenus are now tab-menus; former tab-menus are now collapsible items.

### Admin classes

 - `configureSideMenu` and `buildSideMenu` methods of the `Admin` class have been deprecated; they are replaced by `configureTabMenu` and `buildTabMenu`.

### Remove configureShowField

 - `configureShowField` has been deprecated since a while now, use `configureShowFields` instead => add a `s`.