Provide AP representation of commits, and support committer field

templates/repo/patch.hamlet

@@ -16,13 +16,22 @@ $# <http://creativecommons.org/publicdomain/zero/1.0/>.
   <tr>
     <td>By
     <td>
-      $maybe sharer <- msharer
+      $maybe sharer <- msharerWritten
         ^{sharerLinkW sharer}
       $nothing
-        #{patchAuthorName patch}
+        #{authorName author}
+      $maybe (committer, _) <- patchCommitted patch
+        ;
+        $maybe sharer <- msharerCommitted
+          ^{sharerLinkW sharer}
+        $nothing
+          #{authorName committer}
   <tr>
     <td>At
-    <td>#{showDate $ patchTime patch}
+    <td>
+      #{showDate written}
+      $maybe (_, committed) <- patchCommitted patch
+        ; #{showDate committed}
   <tr>
     <td>Title
     <td>#{patchTitle patch}