A new top bar in the BackOffice

The BackOffice has a new top bar above every screen. It holds the buttons you need everywhere: the language (BG / EN), the light or dark theme, «View site» and «Help». Until now they sat in the top corner of the menu, and «Help» was a menu item. The menu now holds only your pages, and the arrow button next to the ZweiHost name collapses it into a narrow strip of icons. On a phone, «Help» is at the top right, and the language, the theme and «View site» are at the top of the menu.