[m-rev.] for review: change the license of the Mercury-Cairo binding

[Julien Fischer]

For review by anyone.

This change was requested by Peter; as the main author of the code
in question, I have no objections.

----------------------------------------------------------

Change the license for the Mercury-Cario binding.

Change the license the Mercury-Cairo binding to a 2-clause BSD license.
This change has been agreed to by both Peter and myself; we are the
only authors of the affected code.

extras/graphics/mercury_cairo/COPYING.LIB:
     Add the new license.

extras/graphics/mercury-cairo/README:
     Add a link to the license file.

     Fix a typo.

Julien.

diff --git a/extras/graphics/mercury_cairo/COPYING.LIB b/extras/graphics/mercury_cairo/COPYING.LIB
index e69de29..a9a18db 100644
--- a/extras/graphics/mercury_cairo/COPYING.LIB
+++ b/extras/graphics/mercury_cairo/COPYING.LIB
@@ -0,0 +1,24 @@
+Copyright (C) 2010 The University of Melbourne.
+Copyright (C) 2015, 2017-2018 The Mercury team.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+Redistributions of source code must retain the above copyright notice, this
+list of conditions and the following disclaimer.
+
+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 THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 THE COPYRIGHT HOLDER 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.
diff --git a/extras/graphics/mercury_cairo/README b/extras/graphics/mercury_cairo/README
index ccd08f0..85ead51 100644
--- a/extras/graphics/mercury_cairo/README
+++ b/extras/graphics/mercury_cairo/README
@@ -1,6 +1,8 @@
  This directory contains the package `mercury_cairo' which is a Mercury binding
  to the Cairo 2D graphics library.  (See: <http://www.cairographics.org>.)

+See the file COPYING.LIB in this directory for copyright and licensing
+information.

  Building the binding
  ====================
@@ -89,8 +91,8 @@ For example:
      ...


-Backends Submodules
-===================
+Backend Submodules
+==================

  The Mercury binding has submodules that provide image, PDF, PostScript, SVG and
  recording surfaces.  Each surface is represented by a type that is an instance