Porting manual build-trigger to kubectl

@mfojtik @soltysh can you please check this porting effort to kubectl, since your have been working on the kubectl :two_men_holding_hands: 
I see... There's also https://github.com/GoogleCloudPlatform/kubernetes/blob/master/pkg/kubectl/cmd/resource.go#L95 which doesn't require a name. Maybe something like this? https://gist.github.com/csrwng/761952fda9aa69f34f99