x11-toolkits: remove 'Created by' lines

A big Thank You to the original contributors of these ports:

• 1wardd@airmail.net
• Alexander Kabaev <ak03@gte.com>
• Alexander Novitsky <alecn2002@yandex.ru>
• Alexey Dokuchaev <danfe@FreeBSD.org>
• Andreas Kohn <andreas@syndrom23.de>
• Andrew Pantyukhin <infofarmer@FreeBSD.org>
• Anton Berezin <tobez@FreeBSD.org>
• Brian Buchanan <brian@CSUA.Berkeley.EDU>
• Cezary Morga <cm@therek.net>
• Cheng-Lung Sung <clsung@FreeBSD.org>
• Danilo Egea Gondolfo <danilo@FreeBSD.org>
• Dima Sivachenko <dima@Chg.RU>
• Edwin Groothuis <edwin@mavetju.org>
• Eric Anholt <anholt@FreeBSD.org>
• Igor Pokrovsky <ip@doom.homeunix.org>
• James FitzGibbon <jfitz@FreeBSD.org>
• Jean-Sébastien Pédron <dumbbell@FreeBSD.org>
• Joe Marcus Clarke <marcus@FreeBSD.org>
• Juli Mallett
• Kenjiro Cho <kjc@csl.sony.co.jp>
• Kimura Fuyuki <fuyuki@hadaly.org>
• Koop Mast <kwm@FreeBSD.org>
• Lars Koeller <Lars.Koeller@Uni-Bielefeld.de>
• Lubomir Marinov <lubomir_m@abv.bg>
• Marc Recht <marc@informatik.uni-bremen.de>
• Mario Sergio Fujikawa Ferreira <lioux@FreeBSD.org>
• Martin Klaffenboeck <martin.klaffenboeck@gmx.at>
• Martin Matuska <mm@FreeBSD.org>
• Maxim Sobolev <sobomax@FreeBSD.org>
• Michael Grünewald <michipili@gmail.com>
• Michael Johnson <ahze@FreeBSD.org>
• Mike Krutov <neko@takino.org>
• Mike Meyer <mwm@mired.org>
• Olivier Duchateau
• Paul Schmehl <pauls@utdallas.edu>
• Peter Hawkins <thepish@FreeBSD.org>
• Piotr Kubaj <pkubaj@anongoth.pl>
• Radim Kolar
• Rene Ladan <rene@FreeBSD.org>
• Robert C. Noland III <rnoland@FreeBSD.org>
• Simon Barner <barner@gmx.de>
• Stephane Legrand <stephane@FreeBSD.org>
• Sunpoet Po-Chuan Hsieh <sunpoet@FreeBSD.org>
• Thomas Gellekum <tg@FreeBSD.org>
• Tom McLaughlin <tmclaugh@sdf.lonestar.org>
• Vanilla I. Shu <vanilla@MinJe.com.TW>
• Will Andrews <andrews@technologist.com>
• Yukihiro Nakai <nakai@FreeBSD.org>
• Zane C, Bowers <vvelox@vvelox.net>
• asami
• chinsan
• chuckr
• clsung@dragon2.net
• dmitry@karasik.eu.org
• fjoe@FreeBSD.org
• gahr
• gena
• ijliao
• mi
• minter@lunenburg.org
• nivit@users.sourceforge.net
• ports@c0decafe.net
• roland.jesse@gmx.net
• thierry@pompo.net
• vanilla

With hat: portmgr