replace obsolete a name tags with div

This HTML is now obsolete in HTML 5:

```html
<a name="faq0"></a>Section 0: Submitting entries to a new IOCCC
```

Instead we need to use the div HTML elements:

```html
<div id="faq0">Section 0: Submitting entries to a new IOCCC</div>
```

We are testing a fix for the top level HTML files.

Run `make gen_top_html` to perform the above and test under macOS.

TODO: Apply this type of fix across the entire web site if all is well.

contact.html

@@ -118,7 +118,7 @@
 <!-- END: this line ends content from: inc/begin-rightcolumn.default.html -->
 <!-- START: this line starts content from: inc/before-content.default.html -->
 
-    <a name="content"></a>
+    <div id="content">
 
 <!-- END: this line ends content from: inc/before-content.default.html -->
 <!-- START: this line starts content for HTML phase 21 by: bin/pandoc-wrapper.sh via bin/md2html.sh -->
@@ -155,7 +155,10 @@ issue</a>.</p>
 <p>Those FAQ entries will help guide you on how to make public comments
 and suggestion in the relevant places.</p>
 <p>See the above FAQ entries for more details.</p>
-<h1 id="try-mastodon"><a name="mastodon"></a>Try mastodon</h1>
+#
+<div id="mastodon">
+Try mastodon
+</div>
 <p>You may wish to follow us <a href="https://fosstodon.org/@ioccc">IOCCC on Mastodon</a>
 as we use that platform to announce things such as the opening of a new IOCCC
 as well as winning entries of the IOCCC.</p>
@@ -194,6 +197,8 @@ And while using Mastodon is free, the <a href="../judges.html">IOCCC judges</a>
 <!-- END: this line ends content for HTML phase 21 by: bin/pandoc-wrapper.sh via bin/md2html.sh -->
 <!-- START: this line starts content from: inc/after-content.default.html -->
 
+    </div>
+
 <!-- END: this line ends content from: inc/after-content.default.html -->
 <!-- START: this line starts content from: inc/end-rightcolumn.default.html -->
 
@@ -222,7 +227,7 @@ And while using Mastodon is free, the <a href="../judges.html">IOCCC judges</a>
 -->
 
 <div class="footer">
-  <h2><a name="copyright"></a>Copyright and CC BY-SA 4.0 License</h2>
+  <h2><div id="copyright">Copyright and CC BY-SA 4.0 License</div></h2>
   <p>All IOCCC content including this file and web page are:</p>
   <b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Copyright &copy; 1984-2024 by Landon Curt Noll. <a href="https://creativecommons.org/faq/#what-does-some-rights-reserved-mean">Some Rights Reserved</a>.</b>
   <p>This work is licensed by Landon Curt Noll under:</p>