use manage template for "expired" error

dist/templates/manage/manage_expired.html.hbs

@@ -1,7 +0,0 @@
-{{#> layout }}
-  <center><h2>Delete</h2></center>
-
-  <p>
-    This link is invalid or expired. You can <a href="/manage">click here</a> to request a new one.
-  </p>
-{{/layout}}

src/web/manage.rs

@@ -101,7 +101,9 @@ pub fn vks_manage_key(
             Err(e) => MyResponse::ise(e),
         }
     } else {
-        MyResponse::ok("manage/manage_expired", General::default())
+        MyResponse::not_found(
+            Some("manage/manage"),
+            Some("This link is invalid or expired".to_owned()))
     }
 }