Add COPYRIGHT file.

Add COPYRIGHT file in the root directory. Also add NEWS and Changelog
placeholders.

COPYRIGHT

+Files: *
+Copyright: Copyright (C) 2012, 2013 GRNET S.A. All rights reserved.
+License: BSD-2-clause
+
+ Redistribution and use in source and binary forms, with or
+ without modification, are permitted provided that the following
+ conditions are met:
+   1. Redistributions of source code must retain the above
+      copyright notice, this list of conditions and the following
+      disclaimer.
+   2. Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials
+      provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS
+ OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR
+ CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ POSSIBILITY OF SUCH DAMAGE.
+
+ The views and conclusions contained in the software and
+ documentation are those of the authors and should not be
+ interpreted as representing official policies, either expressed
+ or implied, of GRNET S.A.
+
+Files: xseg/drivers/kernel/xseg_posix.c
+Copyright: Copyright (C) 2012, 2013 GRNET S.A. All rights reserved.
+License: GPL
+
+Files: xseg/drivers/kernel/xseg_pthread.c
+Copyright: Copyright (C) 2012, 2013 GRNET S.A. All rights reserved.
+License: GPL
+
+Files: xseg/peers/kernel/xsegbd.c
+Copyright: Copyright (C) 2012, 2013 GRNET S.A. All rights reserved.
+License: GPL
+ This program is free software; 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.
+
+ This program 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 package; if not, write to the Free
+ Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ Boston, MA  02110-1301 USA
+
+ On Debian systems, the full text of the GNU General Public
+ License can be found in the file
+ `/usr/share/common-licenses/GPL'.