Bug#698030: debian-policy: document micro binary packages (udebs).

[Jonathan Nieder <jrnieder@gmail.com>]

Russ Allbery wrote:

> I vote for just calling them "udebs" instead of "micro binary packages."
> The latter sounds more formal, but I don't think anyone calls them that in
> practice, so it may be confusing.  Perhaps:
>
>     udebs (stripped-down binary packages used by the Debian Installer) are
>     not fully covered in this manual and do not comply with all of the
>     requirements discussed here.  See the
>     <url name="Debian Installer internals manual"
>     id="http://d-i.alioth.debian.org/doc/internals/ch03.html";> for more
>     information about them.

Sounds perfect to me.