Please redirect /wiki/df to http://mit.edu/df

Hey Karl, can you set up a server-side permanent redirect from `/wiki/df` to http://mit.edu/df (the new location of that page)? We'll probably forget to edit this copy if there are changes to the mit.edu one, so I'd like to have the redirect in place so we don't have to worry about it.

There's no way to do this in stock Trac, I believe, so you'll need to do this via Apache config or something.
