Install CD, upgrade? dialog needs "Read manual" button.

[Karl Hegbloom]

I think it's nice that when I put an Ubuntu Breezy install CD into the
drive, I get a dialog box that asks if I want to perform an upgrade.  I
think that it ought to also have a "Read the manual" button, that, when
clicked, causes Firefox to visit the documentation on the CD.

There should also be a toplevel 'index.html" file on the CD with links
to the Ubuntu website and the documentation.

-- 
Karl Hegbloom <hegbloom at pdx.edu>