Option in UI to pick a specific CoreOS version

[sputnick]

I'm using kube-cluster with CoreCtl and there is a major bug with Heapster on CoreOS stable since after "1010.6.0" that causes negative CPU metrics (which affects autoscaling, graphs etc). There is no option in CoreCtl.app or Kube-cluster.app to set a specific CoreOS version to avoid the bug - only the release channel which isn't helpful in this case because the latest Beta doesn't work with kube-cluster.app. See kubernetes/kubernetes#30939

This would be a nice enhancement. I've also tried to use the command line tool from within the corectl.app folders on OSX to "corectl pull" with no luck - it just keeps starting a new instance of the app...