dubious copyright notices in emacs.tiff, allegro.lua, etc.

[Paul Eggert]

I did a quick pass through the emacs-26 source files and found the 
following files with dubious copyright notices. We should fix this one 
way or another.

The following image file is used in the GNUstep port:

* nextstep/GNUstep/Emacs.base/Resources/emacs.tiff says 'Copyright (c) 
1998 Hewlett-Packard Company' with no permissions notice. Is this 
because that TIFF file was created by a tool that inserts that copyright 
notice into the image file for some reason? If so, what's the reason? 
Can we use a different tool to create a TIFF-format image that doesn't 
have this copyright issue? I'll CC: Adrian Robert about this, as he 
added that file on 2008-07-15.

The following files were added by Eli on 2015-05-12, as part of a test 
suite for etags. As these are just for testing Emacs, presumably it 
shouldn't be much trouble to remove them if there are real copyright 
issues here:

* test/manual/etags/lua-src/allegro.lua says '-- Copyright (C) 2001-2004 
by David A. Capello' and 'Read "LEGAL.txt" for more information.' but 
there is no LEGAL.txt.

* test/manual/etags/prol-src/natded.prolog says 'Copyright 1995, Bob 
Carpenter' with no permissions notice.

* test/manual/etags/prol-src/ordsets.prolog says 'Copyright(C) 1988, 
Swedish Institute of Computer Science' with no permissions otice.

* test/manual/etags/ps-src/rfc1245.ps says 'Copyright (c) 1986,87,89 by 
Frame Technology, Inc.  All rights reserved.' with no permissions notice.