improve news.html and mastodon info

Added "2024-04-20" news update.

Fixed format for "2023-05-22" news.

Fixed bad links to `judges.html`.

Add "Jump to: top" near the bottom.

The `make gen_top_html` no longer builds `next/rules.html`
nor `next/guidelines.html`.  This is being done by
the `bin/gen-status.sh` tool and `make gen_status`.

Moved `make gen_top_html` after `make gen_status` in the top level
Makefile rules for `make www` and `make quick_www` because
`bin/gen-status.sh` uses the modification date of `news.html` (that
make gen_top_html might modify) when forming `status.json`.

Added FAQ 6.12 for "What is Mastodon and why does IOCCC use it?".

Simplified `contact.html` mastodon info to refer the above FAQ
for further mastodon information.

Changed `bin/gen-top-html.sh` VERSION from "1.4.2 2024-04-21"
to "1.4.3 2024-04-21".

The `bin/gen-status.sh` tool will build `next/rules.html` and/or
`next/guidelines.html` if they are missing or empty.

Changed `bin/gen-status.sh` VERSION from "1.3 2024-04-14"
to "1.4 2024-04-21".

Run `make gen_top_html gen_status` to perform the above.

bin/gen-top-html.sh

@@ -84,11 +84,10 @@ shopt -u dotglob	# disable matching files starting with .
 shopt -u nocaseglob	# disable strict case matching
 shopt -u extglob	# enable extended globbing patterns
 shopt -s globstar	# enable ** to match all files and zero or more directories and subdirectories
-TOP_MD_SET+=("faq")
 
 # set variables referenced in the usage message
 #
-export VERSION="1.4.2 2024-04-21"
+export VERSION="1.4.3 2024-04-21"
 NAME=$(basename "$0")
 export NAME
 export V_FLAG=0
@@ -127,8 +126,6 @@ TOP_MD_SET+=("license")
 TOP_MD_SET+=("markdown")
 TOP_MD_SET+=("news")
 TOP_MD_SET+=("next/README")
-TOP_MD_SET+=("next/guidelines")
-TOP_MD_SET+=("next/rules")
 TOP_MD_SET+=("thanks-for-help")
 #
 export NOOP=