update to the pbuilder page in the packaging guide

[Simon]

I just checked the documentation repository, and it seems that my
patch hasn't been applied.  I'm assuming it's merely been forgotten,
but let me know if that's not the case.

On 5/12/07, Simon <simon80 at gmail.com> wrote:
> Hi, I made this update to the documentation to better facilitate the
> usage of multiple pbuilder tarballs, because the existing
> recommendation interferes with the usage of wrapper scripts like
> pdebuild.
>
>