Fix COPYING based on upstream
see:
http://perl-xml.cvs.sourceforge.net/perl-xml/XML-Grove/COPYING?revision=1.2&view=markup

diff -up XML-Grove-0.46alpha/COPYING.orig XML-Grove-0.46alpha/COPYING
--- XML-Grove-0.46alpha/COPYING.orig	1998-04-02 21:30:20.000000000 +0200
+++ XML-Grove-0.46alpha/COPYING	2012-11-22 14:11:18.393645467 +0100
@@ -1,22 +1,3 @@
 Copyright (C) 1998 Ken MacLeod. All rights reserved.
-
-XML-Grove is free software; you can redistribute it and/or modify it
-under the terms of the Artistic License distributed with Perl version
-5.000 or (at your option) any later version. Please refer to the
-Artistic License that came with your Perl distribution for more
-details.
-
-The Artistic License should have been included in your distribution of
-Perl. It resides in the file named "Artistic" at the top-level of the
-Perl source tree (where Perl was downloaded/unpacked -- ask your
-system administrator if you dont know where this is).  Alternatively,
-the current version of the Artistic License distributed with Perl can
-be viewed on-line on the World-Wide Web (WWW) from the following URL:
-
-    http://www.perl.com/perl/misc/Artistic.html
-
-The latest version of Perl can be obtained on the World-Wide web (WWW)
-from the following URL:
-
-    http://www.perl.com/CPAN/src/latest.tar.gz
-
+This program is free software; you can redistribute it and/or
+modify it under the same terms as Perl itself.
diff -U0 XML-Grove-0.46alpha/ChangeLog.orig XML-Grove-0.46alpha/ChangeLog
--- XML-Grove-0.46alpha/ChangeLog.orig	1999-09-03 23:41:00.000000000 +0200
+++ XML-Grove-0.46alpha/ChangeLog	2012-11-22 14:11:18.394645472 +0100
@@ -0,0 +1,5 @@
+2008-07-20  Ken MacLeod  <ken@bitsko.slc.ut.us>
+
+	* COPYING: Use same license statement as used in individual
+	modules (same terms as perl).
+