Hide package selection screen

[Chris Lumens]

> I can see in anaconda how easy it would be to get rid of this
> screen... it's fairly simple logic where it decides to display it or
> not... less hackish though, where does it pull in the groups it
> displays? Is it out of one of the xml files and I could just modify
> that?

The comps.xml file is where it's mostly driven from, though the
installclasses are involved here too.

- Chris