set pandoc 8 character tab stops for HTML conversion

We add `--tab-stop=8` to all `pandoc(1)` executions in order to set
a better tab stop indentation, especially for tab intended code blocks.

Changed `bin/pandoc-wrapper.sh` VERSION "1.5.3 2024-03-26"
to "1.6 2024-03-31".

Fixed `1991/brnstnd/sorta.README.md` so that the sorta code
is code blocks.

Removed unneeded paragraph group in copyright in `inc/footer.default.html`.

Performed `make www` to perform the above and test under macOS.

2004/vik2/index.html

@@ -283,7 +283,7 @@ the program. The intermediate file size is the size of the output file of the
 <code>cpp</code> <a href="https://en.wikipedia.org/wiki/C_preprocessor">pre-processor</a>. The times
 taken to pre-process the program were measured using GNU <code>cpp</code> on my 2.0MHz P4
 with 512Mb ram and a lot of disk.</p>
-<pre><code>        Generated   Recursive  Max nest  Intermediate
+<pre><code>            Generated   Recursive  Max nest  Intermediate
     Level   prime nrs   includes   count     file size          Time
 
       _3     &lt; 8           2 322       9         74 748            4&quot;
@@ -295,18 +295,18 @@ with 512Mb ram and a lot of disk.</p>
       _9     &lt; 512     1 920 272      38     65 527 808(*)  1h 42&#39;19&quot;(*)
      _10     &lt; 1024    6 826 389     114     63 782 912(*)  2h 47&#39;58&quot;(*)
 
-     (*) Before cpp crashed.</code></pre>
+         (*) Before cpp crashed.</code></pre>
 <!--
 
     Copyright © 1984-2024 by Landon Curt Noll. All Rights Reserved.
 
     You are free to share and adapt this file under the terms of this license:
 
-    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+        Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
 
     For more information, see:
 
-    https://creativecommons.org/licenses/by-sa/4.0/
+        https://creativecommons.org/licenses/by-sa/4.0/
 
 -->
 
@@ -370,7 +370,7 @@ with 512Mb ram and a lot of disk.</p>
 <div class="footer">
   <h2>Copyright and CC BY-SA 4.0 License</h2>
   <p>This file and web page is:</p>
-  <blockquote><p><b>Copyright &copy; 1984-2024 by Landon Curt Noll. All Rights Reserved.</b></p></blockquote>
+  <blockquote><b>Copyright &copy; 1984-2024 by Landon Curt Noll. All Rights Reserved.</b></blockquote>
   <p>You are free to share and adapt this file under the terms of this license:</p>
   <blockquote><b>Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)</b></blockquote>
   <p>For more information, see:</p>