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`.

2020/ferguson1/.entry.json

@@ -9,14 +9,6 @@
 	{ "author_handle" : "Cody_Boone_Ferguson" }
     ],
     "manifest" : [
-	{
-	    "file_path" : "index.html",
-	    "inventory_order" : 10,
-	    "OK_to_edit" : false,
-	    "display_as" : "html",
-	    "display_via_github" : false,
-	    "entry_text" : "entry home page"
-	},
 	{
 	    "file_path" : "prog.c",
 	    "inventory_order" : 20,
@@ -65,6 +57,14 @@
 	    "display_via_github" : false,
 	    "entry_text" : "information for herpetologist hackers"
 	},
+	{
+	    "file_path" : "bugs.html",
+	    "inventory_order" : 100,
+	    "OK_to_edit" : false,
+	    "display_as" : "html",
+	    "display_via_github" : false,
+	    "entry_text" : "current bugs and things that look like bugs but are not"
+	},
 	{
 	    "file_path" : "cannibalism.log.html",
 	    "inventory_order" : 100,
@@ -73,6 +73,14 @@
 	    "display_via_github" : false,
 	    "entry_text" : "about the snake game"
 	},
+	{
+	    "file_path" : "chocolate-cake.html",
+	    "inventory_order" : 100,
+	    "OK_to_edit" : false,
+	    "display_as" : "html",
+	    "display_via_github" : false,
+	    "entry_text" : "double-layered chocolate fudge cake recipe"
+	},
 	{
 	    "file_path" : "crazy.log.html",
 	    "inventory_order" : 100,
@@ -81,6 +89,14 @@
 	    "display_via_github" : false,
 	    "entry_text" : "about some screen dumps"
 	},
+	{
+	    "file_path" : "gameplay.html",
+	    "inventory_order" : 100,
+	    "OK_to_edit" : false,
+	    "display_as" : "html",
+	    "display_via_github" : false,
+	    "entry_text" : "how to play the game"
+	},
 	{
 	    "file_path" : "play.sh",
 	    "inventory_order" : 100,
@@ -97,6 +113,30 @@
 	    "display_via_github" : true,
 	    "entry_text" : "script to reset - preset colors"
 	},
+	{
+	    "file_path" : "spoilers.html",
+	    "inventory_order" : 100,
+	    "OK_to_edit" : false,
+	    "display_as" : "html",
+	    "display_via_github" : false,
+	    "entry_text" : "SPOILER ALERT - about the code"
+	},
+	{
+	    "file_path" : "terminals.html",
+	    "inventory_order" : 100,
+	    "OK_to_edit" : false,
+	    "display_as" : "html",
+	    "display_via_github" : false,
+	    "entry_text" : "terminal capabilities and dimensions and colors"
+	},
+	{
+	    "file_path" : "troubleshooting.html",
+	    "inventory_order" : 100,
+	    "OK_to_edit" : false,
+	    "display_as" : "html",
+	    "display_via_github" : false,
+	    "entry_text" : "troubleshooting the game"
+	},
 	{
 	    "file_path" : "prog.2.c",
 	    "inventory_order" : 150,
@@ -145,6 +185,14 @@
 	    "display_via_github" : false,
 	    "entry_text" : "download entry source"
 	},
+	{
+	    "file_path" : "index.html",
+	    "inventory_order" : 2000000000,
+	    "OK_to_edit" : false,
+	    "display_as" : "html",
+	    "display_via_github" : false,
+	    "entry_text" : "entry home page"
+	},
 	{
 	    "file_path" : ".entry.json",
 	    "inventory_order" : 4294967295,
@@ -175,7 +223,7 @@
 	    "OK_to_edit" : true,
 	    "display_as" : "markdown",
 	    "display_via_github" : true,
-	    "entry_text" : "markdown source for crazy.log.html"
+	    "entry_text" : "markdown source for COMPILING.html"
 	},
 	{
 	    "file_path" : "HACKING.md",
@@ -215,7 +263,7 @@
 	    "OK_to_edit" : true,
 	    "display_as" : "markdown",
 	    "display_via_github" : true,
-	    "entry_text" : "markdown source for chocolate-cake.html"
+	    "entry_text" : "markdown source for cannibalism.log.html"
 	},
 	{
 	    "file_path" : "chocolate-cake.md",
@@ -231,7 +279,7 @@
 	    "OK_to_edit" : true,
 	    "display_as" : "markdown",
 	    "display_via_github" : true,
-	    "entry_text" : "markdown source for deckmyn.html"
+	    "entry_text" : "markdown source for crazy.log.html"
 	},
 	{
 	    "file_path" : "gameplay.md",