Add a file to the LICENSES directory to describe how file licenses
should be described in all the OpenOCD files, using the SPDX
identifier, as well as where all licenses should be in the source
tree for people to refer to (LICENSES/).

This file is mainly copied from the Linux kernel file in
	Documentation/process/license-rules.rst
originally written by Thomas Gleixner <tglx@linutronix.de>, with
specific adaptations for OpenOCD.

Change-Id: I7a98fc756df90dc86dbc6e0c47c009a610a0318d
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/5973


Tested-by: jenkins
Reviewed-by: Tim Newsome <tim@sifive.com>

The script spdxcheck.py (used by checkpatch.pl) searches for the
license files in a dedicated folder, split in the subfolders:
	"preferred", "dual", "deprecated", "exceptions".

Move the GPL-2.0 license from COPYING to the subfolder preferred,
adding the header required by spdxcheck.py.
The header is copied from equivalent file in the Linux kernel,
made by Thomas Gleixner <tglx@linutronix.de>.
Note: the license in COPYING matches exactly
	https://www.gnu.org/licenses/old-licenses/gpl-2.0.txt



Add a minimalist COPYING in the top directory, as required by
automake, pointing to the files in LICENSES.

Change-Id: I1fd0abc57b554d74f0b00fabd6c8c822b2c4acb5
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/5967
Tested-by: jenkins

Change-Id: I429f7fd51f77b0e7c86d7a7f110ca31afd76c173
Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk>
Reviewed-on: http://openocd.zylin.com/1426


Tested-by: jenkins
Reviewed-by: Paul Fertser <fercerpav@gmail.com>

Change-Id: Ic6895b89e8798a3636333dd50a8540eae643719a
Signed-off-by: Dean Glazeski <dnglaze@gmail.com>
Reviewed-on: http://openocd.zylin.com/274


Tested-by: jenkins
Reviewed-by: Øyvind Harboe <oyvindharboe@gmail.com>

git-svn-id: svn://svn.berlios.de/openocd/trunk@64 b42882b7-edfa-0310-969c-e2dbd0fdcd60