[Bug 1174354] Missing Requires: cadvisor

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1174354

--- Comment #1 from Eric Paris  ---
cadvisor is an optional requirement. upstream they use the kubelet to launch a
cadvisor pod on every node instead of having it installed on every node. I'd
like to get there someday.

I'm ok making our cadvisor binary a runtime requirement for now, but I don't
know if it's needed. I dropped it since cadvisor sometimes gets itself into a
bit of a mess and spins at 100% cpu and we don't have the time to run that
down, especially since most of kube works without cadvisor installed...