Copyright for kdav source package in Bionic

Format: http://www.debian.org/doc/packaging-manuals/copyright-format/1.0/

Files: *
Copyright: 2010 Tobias Koenig 
           2014 Gregory Oestreicher 
	   2016 Sandro Knauß 
License: GPL-2+

Files: debian/*
Copyright: 2017 Jonathan Riddell 
License: GPL-2+

License: GPL-2+
 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.
 .
 The complete text of the GNU General Public License version 2
 can be found in `/usr/share/common-licenses/GPL-2'.