Removing debconf-nowarnings option, doesn't provide any advantage to disable this option in the first place.

Rather than a half broken image type, we'll bet our money on having proper
partman recipies support implemented for hdd image types.

Even if we don't make it for wheezy, it's better to not have virtual-hdd
in there and tell users to use the jessie version for proper hdd images.

live-build does too much magic that causes too much effort in
maintaining for stuff that hardly everyone uses.

Rather than 'translating' back and forth and maintaining compatibility
between options of different debootstrap and cdebootstrap versions (and
possibly any other in the future), it's is better to 'off-load' this to
the user.

For non-live specific options passed to the bootstrap tools, we'll
be introducing --debootstrap-options and --cdebootstrap-options
where users can specify their additional options passed to the
respective bootstrap tool, rather than us maintaining them in a
'hardcoded' and selected list.

We don't have proper manpages for lb_*_* commands yet,
rather than having a useless stub for it that's just a
boilerplate and nothing more, let's remove them for now,
and add them back one by one but with full reference content.