Add license headers to all source files

One basic decision is whether to put our names in directly or not. To be more flexible and allow others to join, here what we use in BAT. I like it because it's concise. We should should then add a file to the project that lists the developer team

/*
 * Copyright (C) 2007-2018, the BAT core developer team
 * All rights reserved.
 *
 * For the licensing terms see doc/COPYING.
 * For documentation see http://mpp.mpg.de/bat
 */

And here is a header from EOS that is more verbose but more explicit about who contributed when. What's not good is that it tries to fix the GPL version. We should only say v3 or later

/*
 * Copyright (c) 2011, 2013-2018 Danny van Dyk
 * Copyright (c) 2011 Frederik Beaujean
 *
 * This file is part of the EOS project. EOS is free software;
 * you can redistribute it and/or modify it under the terms of the GNU General
 * Public License version 2, as published by the Free Software Foundation.
 *
 * EOS is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
 * Place, Suite 330, Boston, MA  02111-1307  USA
 */

mtazzari / galario

Add license headers to all source files #131