minor fixes in the template for param graphs

templates/challenge-all-submissions.hamlet

@@ -15,9 +15,12 @@ $if not (null params)
   <h3>Graphs by parameters
 
   $forall param <- params
-     <h4>#{param}
+     <h4>
+      <tt>#{param}
      $forall test <- selectedTests
+       <a name="link-chart-#{param}-#{toPathPiece $ entityKey test}">
        <div id="chart-#{param}-#{toPathPiece $ entityKey test}">
+       [<a href="#link-chart-#{param}-#{toPathPiece $ entityKey test}">direct link</a>]
 
   <script src="/static/js/d3.min.js" charset="utf-8"></script>
   <script src="/static/js/c3.min.js"></script>