Bug#188710: cdebconf-newt-udeb: Multi-page question should have a 'back' button

[Petter Reinholdtsen <pere@hungry.com>]

Package: cdebconf-newt-udeb
Version: 0.34

When the question text is too large to fit on the screen with the
options themselves, the text is first displayed on one page, and the
options are displayed on a second page.  When the options are
displayed, there is no way to go back and have a look at the text
again.  This is annoying, as most people will want to return to read
the text after seeing the options, to check which options is the
correct choice.

I suggest adding a 'Back' button when the question is split in two
like this, to make it possible to go back from the list of options,
and back to the text.