add layer

src/layer.mli

@@ -0,0 +1,21 @@
+type t
+
+val add_to : Map.t -> t -> unit
+
+val remove : t -> unit
+
+val remove_from : Map.t -> t -> unit
+
+val bind_popup : Brr.El.t -> t -> unit
+
+val unbind_popup : t -> unit
+
+val open_popup : t -> unit
+
+val close_popup : t -> unit
+
+val get_popup : t -> Popup.t
+
+val of_jv_t : Jv.t -> t
+
+val to_jv_t : t -> Jv.t