Copyright for libgtksourceviewmm source package in Focal

Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
Source: https://download.gnome.org/sources/gtksourceviewmm/
Upstream-Contact: Murray Cumming 
                  Dodji Seketeli 
                  Rob Page 
                  Jonathon Jongsma 
                  Krzesimir Nowak 
Upstream-Name: gtksourceviewmm

Files: *
Copyright: 2004-2005 Jae Jang
           2005-2006 Rob Page
           2006 Dodji Seketeli
           2009, 2010, 2011 Krzesimir Nowak
           2008 Jonathon Jongsma
           2005-2006 The gtksourceviewmm development team
License: LGPL-2.1+
 This package is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public
 License as published by the Free Software Foundation; either
 version 2.1 of the License, or (at your option) any later version.
 .
 On Debian systems, the complete text of the GNU Lesser General Public
 License can be found in `/usr/share/common-licenses/LGPL-2.1'.