Tor Browser 4.0 make use of the updater and stop directing users to download-easy.html.en

While testing Tor Browser 4.0 I noticed that about:tor still points at TorButton to warn the user that this isn't a recommended (up-to-date) version. This shouldn't happen at all because now TB includes an updater and TorButton should make use of it.

TorButton should just update TB when "Download Tor Browser Bundle Update" when it's clicked. If it fails to get updates, suggest using mirrors or emailing the help desk or even better, gettor when it's up.