Copyright for pychess source package in Mantic

Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
Upstream-Name: pychess
Source: https://pychess.github.io/

Files: *
Copyright: © 2006 Thomas Dybdahl Ahle 
License: GPL-3+
 see `/usr/share/common-licenses/GPL-3'.

Files: debian/*
Copyright: © 2007, Varun Hiremath 
License: GPL-3+
 see `/usr/share/common-licenses/GPL-3'.