improve bin tool script shell variable use

We export shell variables where needed.

We print debug messages of shell variables in the order they were
exported or declared, except for the USAGE shell variable, for those
shell variables that were exported or declared prior to the set of
debug messages of shell variables.

Changed `bin/chk-entry.sh` VERSION from "1.1.3 2024-03-18"
to "1.1.4 2024-03-26".

Changed `bin/gen-authors.sh` VERSION from "1.3.1 2024-03-18"
to "1.3.2 2024-03-26".

Changed `bin/gen-location.sh` VERSION from "1.1.1 2024-03-18"
to "1.1.2 2024-03-26".

Changed `bin/gen-other-html.sh` VERSION from "1.0.1 2024-03-08"
to "1.0.2 2024-03-26".

Changed `bin/gen-sitemap.sh` VERSION from "1.3.2 2024-03-18"
to "1.3.3 2024-03-26".

Changed `bin/gen-status.sh` VERSION from "1.1.1 2024-03-18"
to "1.1.2 2024-03-26".

Changed `bin/gen-years.sh` VERSION from "1.0.2 2024-03-13"
to "1.0.3 2024-03-26".

Changed `bin/md2html.sh` VERSION from "1.1.1 2024-03-09"
to "1.1.2 2024-03-26".

Changed `bin/output-index-author.sh` VERSION from "1.5.1 2024-03-19"
to "1.5.2 2024-03-26".

Changed `bin/output-index-inventory.sh` VERSION from "1.2.2 2024-03-19"
to "1.2.3 2024-03-26".

Changed `bin/output-year-index.sh` VERSION from "1.1.1 2024-03-19"
to "1.1.2 2024-03-26".

Changed `bin/pandoc-wrapper.sh` VERSION from "1.5.2 2024-03-19"
to "1.5.3 2024-03-26".

Changed `bin/quick-readme2index.sh` VERSION from "1.1.2 2024-03-08"
to "1.1.3 2024-03-26".

Changed `bin/readme2index.sh` VERSION from "1.2.1 2024-02-23"
to "1.2.2 2024-02-26".

Changed `bin/sort.gitignore.sh` VERSION from "1.1.2 2024-03-18"
to "1.1.3 2024-03-26".

Changed `bin/status2html.sh` VERSION from "1.1.1 2024-03-19"
to "1.1.2 2024-03-26".

Changed `bin/subst.default.sh` VERSION from "1.2.1 2024-02-23"
to "1.2.2 2024-02-26".

Changed `bin/subst.entry-index.sh` VERSION from "1.3.1 2024-03-19"
to "1.3.2 2024-03-26".

Changed `bin/tar-all.sh` VERSION from "1.1.1 2024-03-18"
to "1.1.2 2024-03-26".

Changed `bin/tar-entry.sh` VERSION from "1.3.1 2024-03-25"
to "1.3.2 2024-03-26".

Changed `bin/tar-year.sh` VERSION from "1.1.1 2024-03-18"
to "1.1.2 2024-03-26".

Changed `bin/all-years.sh` VERSION from "1.0.1 2024-02-23"
to "1.0.2 2024-02-26".

Changed `bin/gen-top-html.sh` VERSION from "1.2.1 2024-03-08"
to "1.2.2 2024-03-26".

Changed `bin/gen-year-index.sh` VERSION from "1.0.3 2024-03-09"
to "1.0.4 2024-03-26".

Changed `bin/subst.year-index.sh` VERSION from "1.1.1 2024-03-19"
to "1.1.2 2024-03-26".

Changed `bin/untar-entry.sh` VERSION from "1.0 2024-03-25"
to "1.0.1 2024-03-26".

bin/gen-other-html.sh

@@ -84,7 +84,7 @@ shopt -s globstar	# enable ** to match all files and zero or more directories an
 
 # set variables referenced in the usage message
 #
-export VERSION="1.0.1 2024-03-08"
+export VERSION="1.0.2 2024-03-26"
 NAME=$(basename "$0")
 export NAME
 export V_FLAG=0
@@ -366,6 +366,7 @@ if [[ $V_FLAG -ge 3 ]]; then
 	echo "$0: debug[3]: TOOL_OPTION[$index]=${TOOL_OPTION[$index]}" 1>&2
     done
     echo "$0: debug[3]: REPO_NAME=$REPO_NAME" 1>&2
+    echo "$0: debug[3]: CD_FAILED=$CD_FAILED" 1>&2
     echo "$0: debug[3]: TOP_FILE=$TOP_FILE" 1>&2
 fi
 
@@ -383,7 +384,7 @@ fi
 # It is a pain to set the EXIT_CODE deep inside a loop, so we write the EXIT_CODE into a file
 # and read the file (setting EXIT_CODE again) after the loop.  A hack, but good enough for our needs.
 #
-TMP_EXIT_CODE=".$NAME.$$.exit.code"
+export TMP_EXIT_CODE=".$NAME.$$.exit.code"
 if [[ $V_FLAG -ge 3 ]]; then
     echo  "$0: debug[3]: temporary exit code: $TMP_EXIT_CODE" 1>&2
 fi
@@ -594,7 +595,7 @@ for YYYY in $(< "$TOP_FILE"); do
 
 	    # determine the number of levels in path of MD_FILE from topdir
 	    #
-	    NO_SLASH=${MD_FILE///}
+	    export NO_SLASH=${MD_FILE///}
 	    LEVEL_CNT=$((${#MD_FILE} - ${#NO_SLASH}))
 	    export LEVEL_CNT
 	    if [[ $LEVEL_CNT -lt 2 ]]; then