Added GPL option and clarification on reason for licensing terms.

diff --git a/licence.shtml b/licence.shtml
index ab794be2eb710f1b58b409a0c675171cc6b97e14..64c1fb71844fb7817b053adaec938c7667fcae3f 100755 (executable)
--- a/licence.shtml
+++ b/licence.shtml
@@ -19,15 +19,25 @@
   </h2>
   <p>
     Unless otherwise noted, permission is granted to copy, distribute and/or
-    modify content on this website under the terms of the <a
+    modify content on this website under the terms of either the <a
     href="http://creativecommons.org/licenses/by-sa/3.0/">Creative Commons
-    Attribution-Sharealike Unported License</a>, Version 3.0 or any later
-    version published by Creative Commons.
+    Attribution-Sharealike Unported License</a>, version 3.0 or any later
+    version published by Creative Commons, or the <a
+    href="http://www.gnu.org/licenses/old-licenses/gpl-2.0.html">GNU General
+    Public License</a>, version 2 or any later version published by the Free
+    Software Foundation.
   </p>
   <p>
-    It's not required by the licence, but if you do use a substantial portion
-    of anything I've published here in a derived work or publish it elsewhere,
-    I would appreciate it if you could tell me about it. :-)
+    The latter option is provided mainly for compatibility with many existing
+    free software projects; if you would like to use anything published here in
+    a project which is licensed incompatibly with both of the licences above,
+    please feel free to <a href="/about.shtml">email me</a>.
+  </p>
+  <p>
+    It's not required by either of the licences, but if you do use a
+    substantial portion of anything I've published here in a derived work or
+    publish it elsewhere, I would appreciate it if you could tell me about it.
+    :-)
   </p>
   <h2>
     Common Exceptions