General
-------

The dist-upgrader is designed to make upgrades for ubuntu (or similar
distributions) easy and painless. It supports both network mode and
cdrom upgrades. The cdromupgrade will ask if it should use the network
or not. There is a wrapper script "cdromugprade" (that assumes the
file of the upgrade life in
CDROM_ROOT/dists/stable/dist-upgrader/binary-all/) that can be put
onto the CD and it will support upgrades directly from the CD.


Configuration
-------------

The DistUpgrade.cfg format is based on the python ConfigParser.

It supports the following sections:

[View] - controls the output 

[Distro] - global distribution specfic options
BaseMetaPkgs: 
  the basic meta-pkgs that must be installed (ubuntu-base usually)
MetaPkgs: 
  packages that define a "desktop" (e.g. ubuntu-desktop)
PostUpgrade{Install,Remove,Purge}: 
  action right after the upgrade was calculated in the cache (marking 
  happens *before* the cache.commit())
ForcedObsoletes: 
  Obsolete packages that the user is asked about after the upgrade (marking 
  happens *after* the cache.commit())
RemoveEssentialOk:
  Those packages are ok to remove even though they are essential
KeepInstalledPkgs:
  If the package was installed before, it should still be installed
  after the upgrade
KeepInstalledSection:
  Packages from this section that were installed should always be
  installed afterwards as well (useful for eg translations)

[$meta-pkg]
KeyDependencies:
  Dependencies that are considered "key" dependencies of the meta-pkg to
  detect if it was installed but later removed by the user
PostUpgrade{Install,Remove,Purge}: 
  s.above
ForcedObsoletes: 
  s.above

[Files] - file specific stuff

[Sources] - how to rewrite the sources.list

[Network] - network specific options

[Backports] - use specific packages for dist-upgrade 
Packages= List of what packages to look for
VersionIdent=Version identification. needs to be uniq, dist-upgrader will
             fetch the version that contains this string
SourcesList=a sources.list fragment that will be placed into 
            /etc/apt/sources.list.d and that contains the backported pkgs