date parsing

src/dune

@@ -1,3 +1,3 @@
 (executable
  (name webcc)
- (libraries omd))
+ (libraries omd ISO8601))

src/webcc.ml

@@ -77,10 +77,11 @@ let process ic oc =
     | None   -> "-"
   in
   let md = Omd.of_channel ic in
+  let date = ISO8601.Permissive.date (lookup_metadata "date") in
   let html = format_post
                ~title:(lookup_metadata "title")
                ~tags:(lookup_metadata "tags")
-               ~date:(lookup_metadata "date")
+               ~date:(ISO8601.Permissive.string_of_date date)
                ~contents:(Omd.to_html md)
   in
   output_string oc html