implemented header and footer

src/html.ml

@@ -8,6 +8,13 @@ let html_of ymd =
          (title (Unsafe.data ymd_title))
          [link ~rel:[`Stylesheet] ~href:"style.css" ();]
       )
-      (body [Unsafe.data ymd_body])
+      (body [
+           header [
+               h1 [Unsafe.data ymd_title];
+               details (summary [Unsafe.data ymd.Logarion.meta.abstract]) [];
+             ];
+           Unsafe.data ymd_body;
+           footer [p []];
+      ])
   in
   Format.asprintf "%a" (Tyxml.Html.pp ()) tyhtml

src/logarion.ml

@@ -39,6 +39,7 @@ let log_meta yaml =
             abstract = "" } in
   let field_map meta (k,v) = match k with
     | "title" -> { meta with title = v }
+    | "abstract" -> { meta with abstract = v }
     | _ -> meta
   in
   List.fold_left field_map m fields