Copyright for gdm3 source package in Focal

This package originally Debianised by Steve Haslam ,
10th March 1999.  It was maintained by Raphaël Hertzog 
until December 1999.  It was maintained by Ryan Murray 
until May 2007.   It is now maintained by the GNOME Team.

It was downloaded from 

Upstream authors:

    William Jon McCann 
    Brian Cameron 
    Ray Strode 

Copyright:
    Copyright © 2002-2018  Red Hat Inc.
    Copyright © 2005-2008  William Jon McCann
    Copyright © 1999-2010  Free Software Foundation, Inc.
    Copyright © 2007-2010  The GNOME project
    Copyright © 1999, 2000 Aladdin Enterprises.
    Copyright © 2007       David Zeuthen
    Copyright © 2006       Ray Strode
    Copyright © 2003-2008  Sun Microsystems, Inc.
    Copyright © 1998-2000  Martin K. Petersen
    Copyright © 2004-2005  James M. Cape
    Copyright © 2000       Helix Code, Inc.
    Copyright © 2008       Matthias Clasen
    Copyright © 2001       Havoc Pennington
    Copyright © 2003-2006  Vincent Untz
    Copyright © 2002       Anders Carlsson
    Copyright © 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald
    Copyright © 2007       Christian Persch
    Copyright © 2007       Andrew Ziem
    Copyright © 2001-2006  Jonathan Blandford

License:

    This package is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This package is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this package; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA

On Debian systems, the complete text of the GNU General
Public License can be found in `/usr/share/common-licenses/GPL-2'.