add modification timestamp

Signed-off-by: Amneesh Singh <natto@weirdnatto.in>

src/site.hs

@@ -133,6 +133,7 @@ postCtx tags =
   tagsField "tags" tags
     --    <> teaserFieldWithSeparator "((.tease.))" "teaser" "content"
     <> dateField "date" "%B %e, %Y"
+    <> modificationTimeField "modified" "%B %e, %Y"
     <> teaserField "teaser" "content"
     <> defaultCtx
 

templates/post.html

@@ -4,9 +4,12 @@
         Posted on $date$
         $if(author)$
             by $author$
-        $endif$ <br>
+        $endif$<br>
         $if(tags)$
             Tags: $tags$
+        $endif$<br>
+        $if(modified)$
+            Last modified on $modified$
         $endif$
     </section>
     <hr>