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.

next/README.md

@@ -0,0 +1,86 @@
+# IOCCC Rules and Guidelines
+
+**IMPORTANT**: Did you read the **Important disclaimers about scope**
+and did you check the current **[IOCCC status](../status.html)**?
+
+* [IOCCC rules](rules.html)
+* [IOCCC guidelines](guidelines.html)
+
+You may also wish to review the
+[mkiocccentry tool repo](https://github.com/ioccc-src/mkiocccentry),
+especially when the  [rules](rules.html) and [guidelines](guidelines.html)
+are official, to be sure you are **using an up to date official mkiocccentry tool set**.
+
+
+# Important disclaimers about scope
+
+
+### When the IOCCC status is closed
+
+When the IOCCC status is closed, the [rules](rules.html) and [guidelines](guidelines.html)
+are **OUT OF DATE**.
+
+They are a **very tentative proposal** for the next IOCCC
+that is **VERY LIKELY** to be updated before the next IOCCC.
+They are are provided as a **tentative** hint at what
+might be used for the next IOCCC.
+
+**IMPORTANT**: All **tentative** [rules](rules.html) and [guidelines](guidelines.html)
+are subject to change by the [IOCCC judges](../judges.html) at any time.
+See both the [IOCCC news](../news.html) and the [IOCCC
+Mastodon](https://fosstodon.org/@ioccc) feed as _sometimes_ the
+[IOCCC judges](../judges.html) _mention_ changes there.
+
+
+### When the IOCCC status is pending
+
+When the IOCCC status is pending, the [rules](rules.html) and [guidelines](guidelines.html) are
+**tentative**.
+
+One might think of them as a **beta** release for the IOCCC
+that is about to open.
+
+**IMPORTANT**: All **tentative** [rules](rules.html) and [guidelines](guidelines.html)
+are subject to change by the [IOCCC judges](../judges.html) at any time.
+See both the [IOCCC news](../news.html) and the [IOCCC
+Mastodon](https://fosstodon.org/@ioccc) feed as _sometimes_ the
+[IOCCC judges](../judges.html) _mention_ changes there.
+
+
+### When the IOCCC status is open
+
+When the IOCCC status is open, the [rules](rules.html) and [guidelines](guidelines.html) are **OFFICIAL**.
+
+Unless some significant problem turns up (such as a need to delay
+in when the IOCCC will close, or some major bug is discovered) they
+will remain **OFFICIAL** for this IOCCC.
+
+**SUGGESTION**: Watch both the [IOCCC news](../news.html) and the [IOCCC
+Mastodon](https://fosstodon.org/@ioccc) feed for the latest news
+about any _mentions_ changes.
+
+
+### When the IOCCC status is judging
+
+When the IOCCC status is judging, the [rules](rules.html) and [guidelines](guidelines.html) are
+for the current IOCCC that is no **longer open for new submissions**.
+
+See the [IOCCC news](../news.html) and well as the [IOCCC
+Mastodon](https://fosstodon.org/@ioccc) feed for updates
+on the IOCCC judging process as well as for the announcement
+for [who won the IOCCC](../years.html).
+
+
+<!--
+
+    Copyright © 1984-2024 by Landon Curt Noll. All Rights Reserved.
+
+    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)
+
+    For more information, see:
+
+	https://creativecommons.org/licenses/by-sa/4.0/
+
+-->