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.

1991/davidguy/index.html

@@ -132,8 +132,7 @@
 <h2 id="author"><a name="author"></a>Author:</h2>
 <ul>
 <li>Name: <a href="../../authors.html#David_Applegate">David Applegate</a><br>
-Location: <a href="../../location.html#US">US</a> - <em>United States of America</em> (<em>United States</em>)
-<br><br></li>
+Location: <a href="../../location.html#US">US</a> - <em>United States of America</em> (<em>United States</em>)</li>
 </ul>
 
 <!-- END: next line ends content generated by: bin/output-index-author.sh -->
@@ -142,16 +141,16 @@ Location: <a href="../../location.html#US">US</a> - <em>United States of America
 <!-- START: this line starts content for HTML phase 21 by: bin/pandoc-wrapper.sh via bin/md2html.sh -->
 
 <h2 id="to-build">To build:</h2>
-<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">./davidguy</span> ip_address:server.screen</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">./davidguy</span> ip_address:server.screen</span></code></pre></div>
 <p>where <code>ip_address</code> in an IP address of an X server.</p>
 <h2 id="try">Try:</h2>
-<div class="sourceCode" id="cb3"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">./davidguy</span> 127.0.0.1:0.0</span></code></pre></div>
+<div class="sourceCode" id="cb3"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a>    <span class="ex">./davidguy</span> 127.0.0.1:0.0</span></code></pre></div>
 <p>Of course, you may need to supply a more reasonable address. :-)</p>
 <h2 id="also-try">Also try:</h2>
-<div class="sourceCode" id="cb4"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb4-1"><a href="#cb4-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> <span class="at">-f</span> davidguy guydavid</span>
-<span id="cb4-2"><a href="#cb4-2" aria-hidden="true" tabindex="-1"></a><span class="ex">./guydavid</span> 127.0.0.1:0.0</span></code></pre></div>
+<div class="sourceCode" id="cb4"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb4-1"><a href="#cb4-1" aria-hidden="true" tabindex="-1"></a>    <span class="fu">cp</span> <span class="at">-f</span> davidguy guydavid</span>
+<span id="cb4-2"><a href="#cb4-2" aria-hidden="true" tabindex="-1"></a>    <span class="ex">./guydavid</span> 127.0.0.1:0.0</span></code></pre></div>
 <p>Can you determine why this makes a difference?</p>
 <h2 id="judges-remarks">Judges’ remarks:</h2>
 <p>We permitted this type of entry to win because:</p>