Copyright for tcl-signal source package in Buster

Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
Upstream-Name: signal_ext
Upstream-Author: Michael Schwartz 
Source: https://www.nyx.net/~mschwart/signal_ext.html

Files: *
Copyright: 1996 Schwartz Computer Consulting Services
 2017 Smithsonian Astrophysical Observatory, Cambridge, MA, USA
License: MIT-alike
 Permission to use, copy, modify, distribute, and sell this software and its
 documentation for any purpose is hereby granted without fee, provided that
 the above copyright notice appear in all copies and that both that
 copyright notice and this permission notice appear in supporting
 documentation, and that the name of SCCS not be used in advertising or
 publicity pertaining to distribution of the software without specific,
 written prior permission.  SCCS makes no representations about the
 suitability of this software for any purpose.  It is provided "as is"
 without express or implied warranty.

Files: debian/*
Copyright: not applicable
License: public-domain
 Debian packaging by Ole Streicher