Add license exemption to link against OpenSSL

LICENSE

@@ -337,3 +337,16 @@ proprietary programs.  If your program is a subroutine library, you may
 consider it more useful to permit linking proprietary applications with the
 library.  If this is what you want to do, use the GNU Lesser General
 Public License instead of this License.
+
+In addition, as a special exception, the copyright holders give
+permission to link the code of portions of this program with the
+OpenSSL library under certain conditions as described in each
+individual source file, and distribute linked combinations
+including the two.
+You must obey the GNU General Public License in all respects
+for all of the code used other than OpenSSL. If you modify
+file(s) with this exception, you may extend this exception to your
+version of the file(s), but you are not obligated to do so. If you
+do not wish to do so, delete this exception statement from your
+version. If you delete this exception statement from all source
+files in the program, then also delete it here.