pykickstart-3 copr

I've tagged and pushed the 3.0 version of pykickstart to github.  I've
also made a copr available with a build in it:

https://copr.fedorainfracloud.org/coprs/clumens/pykickstart-3/

I'll be doing this periodically as I continue working on this branch.
I'm targeting merging it into Fedora proper after F24 is done.  I think
that should give people enough time to adapt their code to the new ways
of doing things.

- Chris