Copyright for mathtex source package in Focal

This package was debianized by Johan Henriksson  on
Sun, 29 Nov 2009 19:20:02 +0100.

Upstream Author:

    John Forkosh 

Copyright:

    Copyright (C) 2009 John Forkosh Associates, Inc

License:

    GPL 3.0

The Debian packaging is (C) 2009, Johan Henriksson  and
is licensed under the GPL, see `/usr/share/common-licenses/GPL'.