Improving links (http -> https) (#425)

templates/example.tmpl

@@ -30,7 +30,7 @@
             {{.DocsRendered}}
           </td>
           <td class="code{{if .CodeEmpty}} empty{{end}}{{if .CodeLeading}} leading{{end}}">
-            {{if .CodeRun}}<a href="http://play.golang.org/p/{{$.URLHash}}"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />{{end}}
+            {{if .CodeRun}}<a href="https://go.dev/play/p/{{$.URLHash}}"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />{{end}}
           {{.CodeRendered}}
           </td>
         </tr>

templates/index.tmpl

@@ -9,7 +9,7 @@
     <div id="intro">
       <h2><a href="./">Go by Example</a></h2>
       <p>
-        <a href="http://go.dev">Go</a> is an
+        <a href="https://go.dev">Go</a> is an
         open source programming language designed for
         building simple, fast, and reliable software.
         Please read the official

templates/site.css

@@ -1,4 +1,4 @@
-/* CSS reset: http://meyerweb.com/eric/tools/css/reset/ */
+/* CSS reset: https://meyerweb.com/eric/tools/css/reset/ */
 html, body, div, span, applet, object, iframe,
 h1, h2, h3, h4, h5, h6, p, blockquote, pre,
 a, abbr, acronym, address, big, cite, code,