build missing HTML files for entries

Setup a simple topnav for missing HTML files for entries.

Added `bin/gen-other-html.sh` to build entry HTML files from
markdown other than README.md to index.html HTML files.

Fixed duplicate link text in `2020/ferguson1/gameplay.md`.

Improved `inc/md2html.cfg` to support building the missing HTML
files for entries.

Added `make gen_other_html` to top level Makefile.
Added `make gen_other_html` to `make quick_www` and `make www`.

Fixed inventory links for year level index.html files.
Changed `bin/output-year-index.sh` VERSION from "1.0.1 2024-02-23"
to "1.1 2024-02-27".

Added missing lines in `manifest.numbers`.  Update the affected
`.entry.json` files.

The manifest (in both `manifest.numbers` and the collection of
manifests from of all entry `.entry.json` files) now match.  Errors
from `make verify_entry_files` will now abort both `make quick_www`
and `make www` rules in the top level `Makefile`.

Changed markdown files in manifest to have an _inventory_order_ of
_2000000000_ so that the `index.html` file will usually appear at
the start of the _Secondary files_ set for the "#inventory" section
of an entry's `index.html` file.

Changed compressed tar files (files that end in _.tar.bz2_) in
manifest to have an _inventory_order_ of _100000_ so that these
files will usually appear at the end of the _Primary files_ set for
the "#inventory" section of an entry's `index.html` file.

Added 'Jump to top` link above the _Primary files_ section.
Changed `bin/output-index-inventory.sh` VERSION from "1.1.1 2024-02-23"
to "1.2 2024-02-27".

Updated HTML files to perform the above via `make www`.

1998/index.html

@@ -242,30 +242,26 @@ Entries of 1998 - The 14th IOCCC</h1>
 <p><strong>Download IOCCC</strong> <a
 href="1998/ioccc.1998.tar.bz2">1998 entry source</a></p>
 <ul>
-<li><a href="1998/banks/index.html">1998/banks</a> - Best of Show</li>
-<li><a href="1998/bas1/index.html">1998/bas1</a> - Best
-Encapsulation</li>
-<li><a href="1998/bas2/index.html">1998/bas2</a> - Best Small
-Program</li>
-<li><a href="1998/chaos/index.html">1998/chaos</a> - Best Object
+<li><a href="banks/index.html">1998/banks</a> - Best of Show</li>
+<li><a href="bas1/index.html">1998/bas1</a> - Best Encapsulation</li>
+<li><a href="bas2/index.html">1998/bas2</a> - Best Small Program</li>
+<li><a href="chaos/index.html">1998/chaos</a> - Best Object
 Orientation</li>
-<li><a href="1998/df/index.html">1998/df</a> - Best Data Hiding</li>
-<li><a href="1998/dlowe/index.html">1998/dlowe</a> - Best Utility</li>
-<li><a href="1998/dloweneil/index.html">1998/dloweneil</a> - Most
-Fun</li>
-<li><a href="1998/dorssel/index.html">1998/dorssel</a> - Obsolescent
+<li><a href="df/index.html">1998/df</a> - Best Data Hiding</li>
+<li><a href="dlowe/index.html">1998/dlowe</a> - Best Utility</li>
+<li><a href="dloweneil/index.html">1998/dloweneil</a> - Most Fun</li>
+<li><a href="dorssel/index.html">1998/dorssel</a> - Obsolescent
 Feature</li>
-<li><a href="1998/fanf/index.html">1998/fanf</a> - Most Obfuscated
+<li><a href="fanf/index.html">1998/fanf</a> - Most Obfuscated
 Translator</li>
-<li><a href="1998/schnitzi/index.html">1998/schnitzi</a> - Best Flow
+<li><a href="schnitzi/index.html">1998/schnitzi</a> - Best Flow
 Control</li>
-<li><a href="1998/schweikh1/index.html">1998/schweikh1</a> - CPP
-Abuse</li>
-<li><a href="1998/schweikh2/index.html">1998/schweikh2</a> - Most
-Erratic Behavior</li>
-<li><a href="1998/schweikh3/index.html">1998/schweikh3</a> - Most Space
+<li><a href="schweikh1/index.html">1998/schweikh1</a> - CPP Abuse</li>
+<li><a href="schweikh2/index.html">1998/schweikh2</a> - Most Erratic
+Behavior</li>
+<li><a href="schweikh3/index.html">1998/schweikh3</a> - Most Space
 Efficient</li>
-<li><a href="1998/tomtorfs/index.html">1998/tomtorfs</a> - Best
+<li><a href="tomtorfs/index.html">1998/tomtorfs</a> - Best
 Self-Documenting</li>
 </ul>
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