ui: impl Timer.schedule function

ui/src/Timer.elm

@@ -1,9 +1,11 @@
-module Timer exposing (Timer, cancel, empty, replace)
+module Timer exposing (Timer, cancel, empty, replace, schedule)
+
+import Process
+import Task
+
 
 {-| Implements an identity to track an asynchronous timer.
 -}
-
-
 type Timer
     = Empty
     | Idle Int
@@ -15,6 +17,11 @@ empty =
     Empty
 
 
+schedule : (Timer -> msg) -> Timer -> Float -> Cmd msg
+schedule message timer millis =
+    Task.perform (always (message timer)) (Process.sleep millis)
+
+
 {-| Replaces the provided timer with a newly created one.
 -}
 replace : Timer -> Timer