SDDMinsteadOfKDM Change pushed back to f21

[Rex Dieter]

At the KDE SIG meeting today, we made the hard decision to push
http://fedoraproject.org/wiki/Changes/SDDMinsteadOfKDM
change/feature back to f21.  There were simply too many sddm-related 
blocker issues that would not be safely resolvable in time for f20 release.

As such, effective immediately, we're implementing
http://fedoraproject.org/wiki/Changes/SDDMinsteadOfKDM#Contingency_Plan
to revert back to using kdm for f20 release.  I just made commits to 
comps-f20 and spin-kickstarts/f20 branch to implement that.

jreznik will send out some followup announcement(s), and relnotes poking 
(thanks).

-- Rex