Copyright and license for the nl_langinfo.3 manual page

Copyright for nl_langinfo.3:

Copyright (c) 2001 Markus Kuhn <mkuhn@acm.org>
and Copyright (c) 2015 Sam Varshavchik <mrsam@courier-mta.com>
and Copyright (c) 2015 Michael Kerrisk <mtk.manpages@gmail.com>

License for nl_langinfo.3:

This is free documentation; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of
the License, or (at your option) any later version.