add hack-a-round for language specified markdown code blocks

When language is specified in a markdown code block such as:

````
```c
    printf("Hello, world!\n");
```
````

is used, the resulting HTML as produced by `pandoc(1)` combined
with our revised `ioccc.css` is not intent the code block well.

A temporary "_hack-a-round_" is to turn the "markdown code language
specifier" into an HTML comment.  For example:

````
```<!---c-->
    printf("Hello, world!\n");
```
````

This commits turns off existing markdown code language specifiers
for now, while preserving our ability to restore them in the future
when a better  "_hack-a-round_" to the "markdown code language
specifier" problem is found.

The HTML impact if this "_hack-a-round_" is to produce HTML that
looks like this:

```
<pre class="&lt;!---c--&gt;"><code> .. </code></pre>
```

We might be able to create a complex set of classes for each markdown
code language (there won't be very many) in `ioccc.css`, or we might
find a more general CSS (or maybe `pandoc(1)`?) solution.

For now, this hack-a-round will have to do.

2020/burton/README.md

@@ -1,6 +1,6 @@
 ## To build:
 
-```sh
+```<!---sh-->
     make
 ```
 
@@ -18,14 +18,14 @@ For more detailed information see [2020 burton bugs](../../bugs.html#2020_burton
 
 ## To use:
 
-```sh
+```<!---sh-->
     ./prog arg ...
 ```
 
 
 ## Try:
 
-```sh
+```<!---sh-->
     ./try.sh
 ```
 
@@ -67,7 +67,7 @@ result?
 
 This code may be tested by:
 
-```sh
+```<!---sh-->
     make test
 ```
 
@@ -107,19 +107,19 @@ Compiles cleanly under `clang -Wall -Weverything -pedantic`, but you need to add
 
 On a little-endian machine:
 
-```sh
+```<!---sh-->
     clang -include stdio.h -include stdlib.h -Wall -Weverything -pedantic -DB=6945503773712347754LL -DI=5859838231191962459LL -DT=0 -DS=7 -o prog prog.c
 ```
 
 On a big-endian machine:
 
-```sh
+```<!---sh-->
     clang -include stdio.h -include stdlib.h -Wall -Weverything -pedantic -DB=7091606191627001958LL -DI=6006468689561538903LL -DT=1 -DS=0 -o prog_be prog.c
 ```
 
 You might be interested to compile it both ways on the same host, and try:
 
-```sh
+```<!---sh-->
     ./prog 1; ./prog_be 1
 ```
 

2020/burton/index.html

@@ -141,15 +141,15 @@ 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></span></code></pre></div>
+<pre class="&lt;!---sh--&gt;"><code>    make</code></pre>
 <h3 id="bugs-and-misfeatures">Bugs and (Mis)features:</h3>
 <p>The current status of this entry is:</p>
 <pre><code>    STATUS: INABIAF - please **DO NOT** fix</code></pre>
 <p>For more detailed information see <a href="../../bugs.html#2020_burton">2020 burton bugs</a>.</p>
 <h2 id="to-use">To use:</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">./prog</span> arg ...</span></code></pre></div>
+<pre class="&lt;!---sh--&gt;"><code>    ./prog arg ...</code></pre>
 <h2 id="try">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="ex">./try.sh</span></span></code></pre></div>
+<pre class="&lt;!---sh--&gt;"><code>    ./try.sh</code></pre>
 <h2 id="alternate-code">Alternate code:</h2>
 <p>By default, the program works for Little Endian machines. This alternate build
 is for Big Endian machines (that works whether you have LE or BE).</p>
@@ -170,7 +170,7 @@ value that results when the two magic constants are <code>XOR</code>ed.</p>
 choosing new constants, but using the same computation generate a reversed
 result?</p>
 <p>This code may be tested by:</p>
-<div class="sourceCode" id="cb5"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a>    <span class="fu">make</span> test</span></code></pre></div>
+<pre class="&lt;!---sh--&gt;"><code>    make test</code></pre>
 <h2 id="authors-remarks">Author’s remarks:</h2>
 <p>Invoke this with a single non-negative integer less than 256, and a useful
 transformation occurs.</p>
@@ -189,11 +189,11 @@ display strange results with more than one argument.</p>
 <p>Compiles cleanly under <code>clang -Wall -Weverything -pedantic</code>, but you need to add
 <code>--include stdio.h --include stdlib.h</code> for the <code>printf(3)</code> and <code>atoi(3)</code>.</p>
 <p>On a little-endian machine:</p>
-<div class="sourceCode" id="cb6"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb6-1"><a href="#cb6-1" aria-hidden="true" tabindex="-1"></a>    <span class="fu">clang</span> <span class="at">-include</span> stdio.h <span class="at">-include</span> stdlib.h <span class="at">-Wall</span> <span class="at">-Weverything</span> <span class="at">-pedantic</span> <span class="at">-DB</span><span class="op">=</span>6945503773712347754LL <span class="at">-DI</span><span class="op">=</span>5859838231191962459LL <span class="at">-DT</span><span class="op">=</span>0 <span class="at">-DS</span><span class="op">=</span>7 <span class="at">-o</span> prog prog.c</span></code></pre></div>
+<pre class="&lt;!---sh--&gt;"><code>    clang -include stdio.h -include stdlib.h -Wall -Weverything -pedantic -DB=6945503773712347754LL -DI=5859838231191962459LL -DT=0 -DS=7 -o prog prog.c</code></pre>
 <p>On a big-endian machine:</p>
-<div class="sourceCode" id="cb7"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a>    <span class="fu">clang</span> <span class="at">-include</span> stdio.h <span class="at">-include</span> stdlib.h <span class="at">-Wall</span> <span class="at">-Weverything</span> <span class="at">-pedantic</span> <span class="at">-DB</span><span class="op">=</span>7091606191627001958LL <span class="at">-DI</span><span class="op">=</span>6006468689561538903LL <span class="at">-DT</span><span class="op">=</span>1 <span class="at">-DS</span><span class="op">=</span>0 <span class="at">-o</span> prog_be prog.c</span></code></pre></div>
+<pre class="&lt;!---sh--&gt;"><code>    clang -include stdio.h -include stdlib.h -Wall -Weverything -pedantic -DB=7091606191627001958LL -DI=6006468689561538903LL -DT=1 -DS=0 -o prog_be prog.c</code></pre>
 <p>You might be interested to compile it both ways on the same host, and try:</p>
-<div class="sourceCode" id="cb8"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb8-1"><a href="#cb8-1" aria-hidden="true" tabindex="-1"></a>    <span class="ex">./prog</span> 1<span class="kw">;</span> <span class="ex">./prog_be</span> 1</span></code></pre></div>
+<pre class="&lt;!---sh--&gt;"><code>    ./prog 1; ./prog_be 1</code></pre>
 <!--
 
     Copyright © 1984-2024 by Landon Curt Noll. All Rights Reserved.