add rules, guidelines, fix HTML code, move compressed tarball in inventory

By changing the _inventory_order_ of the compressed tarball from
**100000** to **1415926535**, the compressed tarball will land at
the top of the secondary file list and remain still easy to find.

Updated the `manifest.numbers` spreadsheet and rebuilt
the `.entry.json` files.

Added `next/` directory to hold the next IOCCC rules and guidelines.
Added `next/README.md` that `bin/gen-top-html.sh` uses to form
the `next/index.html` file.

Added _Rules and Guidelines_ link to the sidenav bar to link to the
`next/index.html` file.

Added _IOCCC Rules_ as `next/rules.md` that `bin/gen-top-html.sh`
uses to form the `next/rules.html` file.

Added _IOCCC Guidelines_ as `next/guidelines.md` that `bin/gen-top-html.sh`
uses to form the `next/guidelines.html` file.

Changed `bin/gen-top-html.sh` VERSION from "1.2.4 2024-04-13"
to "1.3 2024-04-14".

Prevent `pandoc(1)` from interpreting the commented out language
of a markdown code block as a code class.  So a markdown such as:

````
``` <!---sh-->
...
```
````

that produced HTML of the form:

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

will now produce HTML of the form:

```html
<pre><code>...</code></pre>
```

NOTE: Before when the language of a markdown code block
was not commented, the HTML produced by `pandoc(1)` was
oddly indented with extra whitespace on the first line
of the code block.  While commenting out the language
of the code block removed some of the odd intending,
it left a weird class in the HTML pre block that
surrounded the HTML code block.  This hack prevents
`pandoc(1)` from assigning a class to the HTML pre block.

Changed `in/md2html.sh` VERSION from "1.2.1 2024-04-13"
to "1.3 2024-04-14".

Added `make gen_sitemap` to end of both `make www` and `make
quick_www` in top level Makefile.

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

**IMPORTANT NOTE**: The current `next/rules.md` and `next/guidelines.md`
are simply the 2020 IOCCC Rules and Guidelines converted into
markdown form.  There are **NOT** the Rules and Guidelines that
will be used the IOCCC MOCK, nor the next IOCCC.

TODO: Improve the `bin/gen-status.sh` tool to modify the top of the
      `next/rules.md` and `next/guidelines.md` files to keep them
      in sync with the _contest_status_ as found in `status.json`.

TODO: Improve the look and feel of the `next/rules.md` and
      `next/guidelines.md` markdown files.

2020/yang/index.html

@@ -88,6 +88,7 @@
     <div class="sidenav">
       <a href="../../news.html">IOCCC News</a>
       <a href="../../status.html">Contest status</a>
+      <a href="../../next/index.html">Rules and Guidelines</a>
       <a href="../../faq.html#submit">How to enter the IOCCC</a>
       <a href="../../faq.html">FAQ</a>
     </div>
@@ -141,14 +142,14 @@ 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>
-<pre class="&lt;!---sh--&gt;"><code>    make</code></pre>
+<pre><code>    make</code></pre>
 <h2 id="to-use">To use:</h2>
-<pre class="&lt;!---sh--&gt;"><code>    ./prog [PIN] &lt; input.txt &gt; output.c</code></pre>
+<pre><code>    ./prog [PIN] &lt; input.txt &gt; output.c</code></pre>
 <h2 id="try">Try:</h2>
-<pre class="&lt;!---sh--&gt;"><code>    ./try.sh</code></pre>
+<pre><code>    ./try.sh</code></pre>
 <p>The author provided the file <a href="cppp.cc">cppp.cc</a> which can preprocess the
 generated output to make them more acceptable to typical compilers. To build:</p>
-<pre class="&lt;!---sh--&gt;"><code>    make cppp</code></pre>
+<pre><code>    make cppp</code></pre>
 <p>See the author’s remarks for more details.</p>
 <h2 id="judges-remarks">Judges’ remarks:</h2>
 <p>You might think of this entry as code obfuscater with a code.
@@ -159,7 +160,7 @@ What is compiling this entry about?
 spoiler</a> that shows how this entry was written.</p>
 <h2 id="authors-remarks">Author’s remarks:</h2>
 <h3 id="synopsis">Synopsis</h3>
-<pre class="&lt;!---sh--&gt;"><code>    echo &quot;Hello world&quot; | ./prog 12345 &gt; encoded.c
+<pre><code>    echo &quot;Hello world&quot; | ./prog 12345 &gt; encoded.c
 
     gcc -DPIN=12345 encoded.c -o ./decoded &amp;&amp; ./decoded</code></pre>
 <h3 id="details">Details</h3>
@@ -169,10 +170,10 @@ spoiler</a> that shows how this entry was written.</p>
     where [PIN] is an integer in the range of 1..65535</code></pre>
 <p>When run with an encoding PIN (first command line argument), Mile will
 read bytes from <code>stdin</code> and generate C code on <code>stdout</code>. Example:</p>
-<pre class="&lt;!---sh--&gt;"><code>    echo &quot;Hello, world!&quot; | ./prog 56789 &gt; encoded.c</code></pre>
+<pre><code>    echo &quot;Hello, world!&quot; | ./prog 56789 &gt; encoded.c</code></pre>
 <p>This generated code will reproduce the same input bytes on <code>stdout</code> when
 executed, if it was compiled with the same encoding PIN.</p>
-<pre class="&lt;!---sh--&gt;"><code>    gcc -DPIN=56789 encoded.c -o decoded</code></pre>
+<pre><code>    gcc -DPIN=56789 encoded.c -o decoded</code></pre>
 <p>The generated code reconstructs all data at compile time by seeding a
 random number generator with the given PIN to reproduce the input bytes,
 and simply does one <code>fwrite(3)</code> call at run time to print those bytes. Not
@@ -260,10 +261,10 @@ then compile it with a c++ compiler of your choice.</p>
 <li><a href="https://github.com/ioccc-src/temp-test-ioccc/blob/master/2020/yang/try.sh">try.sh</a> - how to run</li>
 <li><a href="https://github.com/ioccc-src/temp-test-ioccc/blob/master/2020/yang/cppp.cc">cppp.cc</a> - encode large file C Pre-PreProcessor source</li>
 <li><a href="spoiler.html">spoiler.html</a> - SPOILER WARNING</li>
-<li><a href="2020_yang.tar.bz2">2020_yang.tar.bz2</a> - download entry tarball</li>
 </ul>
 <h2 id="secondary-files">Secondary files</h2>
 <ul>
+<li><a href="2020_yang.tar.bz2">2020_yang.tar.bz2</a> - download entry tarball</li>
 <li><a href="index.html">index.html</a> - this web page</li>
 <li><a href="https://github.com/ioccc-src/temp-test-ioccc/blob/master/2020/yang/README.md">README.md</a> - markdown source for this web page</li>
 <li><a href="https://github.com/ioccc-src/temp-test-ioccc/blob/master/2020/yang/.entry.json">.entry.json</a> - description of entry in JSON</li>