improved indentation and whitespace for markdown code blocks

All code blocks in markdown have been intended by at least 4 spaces.

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 from "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`.

Fixed excess whitespace after list Author on entry `index.html` page.

Changed `bin/output-index-author.sh` VERSION from "1.5.2 2024-03-26"
to "1.6 2024-03-31".

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

TODO: Fix the problem of the initial line of code being extra intended.
TODO: Fix excess whitespace around code that is inline.

1993/jonth/index.html

@@ -132,8 +132,7 @@
 <h2 id="author"><a name="author"></a>Author:</h2>
 <ul>
 <li>Name: <a href="../../authors.html#Jon_Thingvold">Jon Thingvold</a><br>
-Location: <a href="../../location.html#NO">NO</a> - <em>Kingdom of Norway</em> (<em>Norway</em>)
-<br><br></li>
+Location: <a href="../../location.html#NO">NO</a> - <em>Kingdom of Norway</em> (<em>Norway</em>)</li>
 </ul>
 
 <!-- END: next line ends content generated by: bin/output-index-author.sh -->
@@ -146,9 +145,9 @@ Location: <a href="../../location.html#NO">NO</a> - <em>Kingdom of Norway</em> (
 compile. macOS users running Mountain Lion and later will need to download and
 install <a href="https://www.xquartz.org">XQuartz</a> in order to compile and run this
 entry.</p>
-<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="fu">make</span> all</span></code></pre></div>
+<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a>    <span class="fu">make</span> all</span></code></pre></div>
 <h2 id="to-use">To use:</h2>
-<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="ex">./jonth</span>                 <span class="co"># must be run on an X11 server</span></span></code></pre></div>
+<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a>    <span class="ex">./jonth</span>     <span class="co"># must be run on an X11 server</span></span></code></pre></div>
 <h2 id="judges-remarks">Judges’ remarks:</h2>
 <p>Use <code>h</code> and <code>l</code> to shift objects left or right. Use <code>k</code> to
 rotate and press SPACE to drop.</p>