Add note block

scss/partials/_boxes.scss

@@ -6,6 +6,7 @@ $types: (
     exercice:   (color: $pale-yellow, title-color: $yellow, icon: "\f040"),
     answer:     (color: $pale-turq,   title-color: $turq,   icon: "\f00c"),
     summary:    (color: $pale-blue,   title-color: $blue,   icon: "\f02e"),
+    note:       (color: $pale-blue,   title-color: $blue,   icon: "\f249"),
     hint:       (color: $pale-grey,   title-color: $grey,   icon: "\f05a"),
     important:  (color: $pale-red,    title-color: $red,    icon: "\f005"),
     caution:    (color: $pale-orange, title-color: $orange, icon: "\f071"),