autoconf: maint: advertise GNU in README

From a1b9ba479069d95de5cf13ffa2655893040bad59 Mon Sep 17 00:00:00 2001
From: Eric Blake <[EMAIL REDACTED]>
Date: Mon, 10 May 2021 15:50:42 -0500
Subject: [PATCH] maint: advertise GNU in README

* README: Add section to attract more people towards the GNU project.
Inspired by a suggestion from Jose E. Marchesi <> on
the gnu-prog-discuss mailing list.
 README | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/README b/README
index fd16df7c..2cedb951 100644
--- a/README
+++ b/README
@@ -40,7 +40,7 @@ found in <>, and
 similarly for the other mailing lists.
 Autoconf is released under the General Public License version 3 (GPLv3+).
 Additionally, Autoconf includes a licensing exception in some of its
 source files; see the respective copyright notices for how your
@@ -55,6 +55,25 @@ For more licensing information, see
 For any copyright year range specified as YYYY-ZZZZ in this package
 note that the range specifies every single year in that closed interval.
+GNU Project notice
+Autoconf is part of the GNU Operating System, developed by the GNU Project.
+If you are the author of an awesome program and want to join us in
+writing Free (libre) Software, please consider making it an official
+GNU program and become a GNU Maintainer.  Instructions on how to do
+this are here:
+Don't have a program to contribute?  Look at all the other ways to help:
+And to learn more about Free (libre) Software in general, please read
+and share this page:
+We are looking forward to hacking with you!
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