Move alpha channel to stable
Move alpha channel to stable

In particular, this ensures that kops 1.6 users get k8s 1.6.2

faraazkhan/kops,gambol99/kops,aledbf/kops,chrislovecnm/kops,reactiveops/kops,mad01/kops,faraazkhan/kops,blakebarnett/kops,robinpercy/kops,BradErz/kops,tsupertramp/kops,aledbf/kops,aledbf/kops,chrislovecnm/kops,mad01/kops,mad01/kops,blakebarnett/kops,andrewsykim/kops,BradErz/kops,austinmoore-/kops,MadDogTechnology/kops,austinmoore-/kops,tsupertramp/kops,pdh/kops,robinpercy/kops,MadDogTechnology/kops,tsupertramp/kops,austinmoore-/kops,kubernetes/kops,gambol99/kops,pdh/kops,andrewsykim/kops,faraazkhan/kops,blakebarnett/kops,chrislovecnm/kops,faraazkhan/kops,robinpercy/kops,reactiveops/kops,MadDogTechnology/kops,robinpercy/kops,kubernetes/kops,MadDogTechnology/kops,gambol99/kops,tsupertramp/kops,justinsb/kops,andrewsykim/kops,reactiveops/kops,austinmoore-/kops,BradErz/kops,reactiveops/kops,blakebarnett/kops,kubernetes/kops,chrislovecnm/kops,aledbf/kops,gambol99/kops,mad01/kops,justinsb/kops,BradErz/kops,justinsb/kops,pdh/kops,andrewsykim/kops,pdh/kops