message: Add a link to the document in the timings report
diff: @@ -642,6 +642,10 @@ h1 {
  border-bottom: 1px solid #c0c0c0;
  }
  +h1 > a {
  + font-size: 14px;
  +}
  +
  .graph {
  display: block;
  }
  @@ -732,7 +736,7 @@ h1 {
  </head>
  <body>
  -<h1>Cargo Build Timings</h1>
  +<h1>Cargo Build Timings <a href="https://doc.rust-lang.org/nightly/cargo/reference/timings.html">Documentation</a></h1>
  "#;
  static HTML_CANVAS: &str = r#"
  