full CDs.
* Make the full CD have apt-mirror-setup in its udeb_exclude file, to avoid
that component being installed to satisfy apt-setup's dependency on it (I
hope), so that the user is not unncessarily asked for a mirror during a
full CD install, but is still asked for one during installs from the
smaller CDs.
Only enable the rescue isolinux targets for etch.
I hope at least some of the etch stuff (like tools/boot/etch) can be used
for the daily CD builds that build using d-i daily builds.