yum-presto and comps

[Jens Petersen]

In F12 we shipped yum-presto in @gnome-desktop - a kind of a compromise I guess.
Presto/deltarpm is very useful for machines with low net connectivity to mirrors
but enough resources to rebuild rpms.

But yum-presto is not a desktop package at all and certainly does not
belong in the gnome-desktop group. [1]

Perhaps the right approach for f13 is to install yum-presto by default
but to disable it by default?  Lighter compression might also
help to reduce the resource requirements for older machines?

Jens

[1] https://bugzilla.redhat.com/show_bug.cgi?id=549659