Copyright for xsnow source package in Bionic

This is a Debian prepackaged version of xsnow.

This package was put together by Joey Hess  and later
maintained by Martin Schulze , Adrian Bunk ,
Randall Donald , and Cai Qian . Current
maintained by Martin Lazar .

It was downloaded from http://dropmix.xs4all.nl/rick/Xsnow/

This package is not part of Debian main because its license only allows
modifications for the purpose of packaging but not arbitrary modifications.

Copyright:

   Copyright 1984, 1988, 1990, 1993-1995, 2000-2001 by Rick Jansen, all rights
   reserved. 

   This means Xsnow is available freely and you may give it to other
   people as is, but I retain all rights. Therefore it does not classify
   as 'Public Domain' software. It *is* allowed to package Xsnow for
   Unix/Linux distributions, CD-Roms etc, and to make the necessary
   changes to makefiles etc. to facilitate this.

   Permission to use and distribute Robin Hogan's toon_root.c under the terms
   of the xsnow license when used as part of xsnow has been obtained.