Latest webkitwindow to be able to use '<number> <text>' as response status.

83ebd11a05ee932deb79902b4908c71951924b95
First attempt at supporting WSGI to write framed terminal applications.

Things that need improvement:
- '/' as a url does not work (is reserved for the root document)
- do not use meta-refresh to redirect to url, pass url directly in the
  iframe mode switch
- debugging such an app must be easier, e.g. show stacktraces somewhere
- integrate with websockets (autobahn)