o  ensure that host & domain names are properly overridable despite DHCP

=-=-=-=-=-=-

Here we have the old dashslashdash TODO list

 o  class to add an ssh console

 o  -/opts=
      things like nolocal to ignore the presence of a local debian-dsd-preseed
      host -- handy for testing
 
 o  -/default=
      might be handy to allow a CD to be setup with a case in /dashslashdash.sh
      that sets things that would make things go more smoothly on several
      local sites, rather than having to make several separately tweaked
      CDs -- of course, since this only needs /dashslashdash.sh to be changed
      there's nothing stopping people doing this themselves.  Adding targets
      to the isolinux.cfg named after the location would be rather nice, so
      one could go:

         boot: site5

      and have it know the proxy to use, and a spare IP address to use, because
      their DHCP setup is broken, say.

 o  make the dsd_fetch_file and the preseed.sh stuff use a common script, so
    there only needs to be one thing that know how to get all types of URL
    so that we can do stuff like using proxies from the outset, etc.

 o  work out a way of letting a script know which class it was downloaded by
    so we can make some of this a little bit OO-ish
 
 o  support scripts for doing things somewhat like FAI's fcopy

 o  a shell library for including into all these similar looking scripts

 o  work out how to prompt the user, so I can add a "hit return to continue"
    when trying to debug scripts

 o  perhaps make dsd_fetch_file support some form of variable substitution
    so that one might ask it to retrive a file:

       local/files/authorised_keys/%H

    and it actually downloads the one named after the hostname, say.

    It might be good to be able to have it attempt to grab a file for each
    class a machine was in, although dealing with the resulting files in
    a sane manner will need some thought -- perhaps a similar expansion
    on the target, and some tools based on the runnparts approach would
    do the trick.