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/bugs.html

@@ -232,8 +232,8 @@ me and I figured I better note it.</p>
 second pointing to where it happens and the third being what’s left after the
 rest of the snake has gone through). Doing <code>SHED=100 SHEDS=-1</code>:</p>
 <pre><code>ooooooooo&gt;ooo&gt;
-     ^
-     &gt;</code></pre>
+         ^
+         &gt;</code></pre>
 <p>The <code>^</code> points to the part that’s split from the snake and which will be
 there on its own after the snake passes through it. Here’s an example with
 it being <code>SHEDS=-3</code>:</p>
@@ -342,11 +342,11 @@ but it is very much appreciated and it means a great deal to me. Cheers.)</p>
 
     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/
 
 -->
 
@@ -383,7 +383,7 @@ but it is very much appreciated and it means a great deal to me. Cheers.)</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>