Add an exception to the LGPL.

COPYING

@@ -1,3 +1,14 @@
+The libfreefare source code is licensed by the *modified* GNU Lesser
+General Public License (LGPL), text provided below. A special exception
+to the LGPL is included to allow you to distribute a combined work that
+includes the libfreefare without being obliged to provide the source
+code for any proprietary components. The exception text is also included
+at the bottom of this file.
+
+The LGPL license text follows.
+
+------------------------------------------------------------------------
+
 		   GNU LESSER GENERAL PUBLIC LICENSE
                        Version 3, 29 June 2007
 
@@ -163,3 +174,38 @@ whether future versions of the GNU Lesser General Public License shall
 apply, that proxy's public statement of acceptance of any version is
 permanent authorization for you to choose that version for the
 Library.
+
+------------------------------------------------------------------------
+
+The libfreefare LGPL Exception Text:
+
+Any libfreefare source code, whether modified or in it's original
+release form, or whether in whole or in part, can only be distributed by
+you under the terms of the GNU Lesser General Public License plus this
+exception. An independent module is a module which is not derived from
+or based on the libfreefare.
+
+Clause 1:
+
+Linking the libfreefare statically or dynamically with other modules is
+making a combined work based on the libfreefare. Thus, the terms and
+conditions of the GNU Lesser General Public License cover the whole
+combination.
+
+As a special exception, the copyright holder of the libfreefare gives
+you permission to link the libfreefare with independent modules that
+communicate with the libfreefare solely through the libfreefare API
+interface, regardless of the license terms of these independent modules,
+and to copy and distribute the resulting combined work under terms of
+your choice, provided that:
+
+  - Every copy of the combined work is accompanied by a written
+    statement that details to the recipient the version of the
+    libfreefare used and an offer by yourself to provide the libfreefare
+    source code (including any modifications you may have made) should
+    the recipient request it.
+
+  - The independent modules add significant and primary functionality to
+    the libfreefare and do not merely extend the existing functionality
+    already present in the libfreefare.
+