Copyright for xcftools source package in Xenial

Package: xcftools
Author: Henning Makholm 

Files: *
Copyright: (C) 2006-2009 Henning Makholm 
License: Public Domain

Files: gimp/*
Copyright: (C) 1995-1997 Peter Mattis and Spencer Kimball
License: GPL-2+

Files: debian/*
Copyright:
    (C) 2006 Henning Makholm 
    (C) 2009 Jan Hauke Rahm 
License: GPL-2+

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