Improve left bar layout in admin and registration layout
Created by: adipasquale
https://trello.com/c/oRwiQaLW/1062-am%C3%A9liorer-lui-du-menu-lat%C3%A9ral
Created by: adipasquale
https://trello.com/c/oRwiQaLW/1062-am%C3%A9liorer-lui-du-menu-lat%C3%A9ral