Use https link for discussion forum

README.md

@@ -16,7 +16,7 @@ new functionality.
 You can find more information (and the
 [manual](http://codemirror.net/doc/manual.html)) on the [project
 page](http://codemirror.net). For questions and discussion, use the
-[discussion forum](http://discuss.codemirror.net/).
+[discussion forum](https://discuss.codemirror.net/).
 
 See
 [CONTRIBUTING.md](https://github.com/codemirror/CodeMirror/blob/master/CONTRIBUTING.md)

index.html

@@ -162,7 +162,7 @@
   license that CodeMirror uses.</p>
 
   <p>Discussion around the project is done on
-  a <a href="http://discuss.codemirror.net">discussion forum</a>.
+  a <a href="https://discuss.codemirror.net">discussion forum</a>.
   There is also
   the <a href="http://groups.google.com/group/codemirror-announce">codemirror-announce</a>
   list, which is only used for major announcements (such as new