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.

2020/ferguson1/gameplay.html

@@ -522,11 +522,11 @@ could also set the max size to be the highest possible by saying</p>
 perfect: the snake after all does not leave gaps and the game does not support
 diagonal movement and I also made a mistake and had to modify what I was aiming
 for. But you can consider this mode drawing or practice mode.</p>
-<pre><code>       oooooooooo   ooooo    o  oo  ooooo
-       o     o  oo  o   oo   o ooo  o
-       oooo  o   oo ooooooo  oooo   ooooo
-          o  o    ooo     oo o ooo  o
-       oooo  o     oo      ooo  oooooooo&gt;</code></pre>
+<pre><code>           oooooooooo   ooooo    o  oo  ooooo
+           o     o  oo  o   oo   o ooo  o
+           oooo  o   oo ooooooo  oooo   ooooo
+              o  o    ooo     oo o ooo  o
+           oooo  o     oo      ooo  oooooooo&gt;</code></pre>
 <h2 id="gameplay-mode-computer-playing-automatic-mode-photosensitive-epilepsystimulation-overload-trigger"><a name="auto" href="#toc">Gameplay mode: Computer playing / Automatic mode (Photosensitive epilepsy/Stimulation overload trigger)</a></h2>
 <p><strong>Photosensitive epilepsy/stimulation overload trigger warning:</strong>
 For those who have epilepsy or are susceptible to stimulation overload from
@@ -713,11 +713,11 @@ years ago but I know it’s true now. <strong>Believe in yourself. Always.</stro
 
     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/
 
 -->
 
@@ -754,7 +754,7 @@ years ago but I know it’s true now. <strong>Believe in yourself. Always.</stro
 <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>