update docs to ensure aks/aks-engine autoscaler users provide the resource group name correctly
update docs to ensure aks/aks-engine autoscaler users provide the resource group name correctly

mmerrill3/autoscaler,bskiba/autoscaler,kubernetes/autoscaler,kubernetes/autoscaler,kubernetes/autoscaler,bskiba/autoscaler,bskiba/autoscaler,mmerrill3/autoscaler,mmerrill3/autoscaler,kubernetes/autoscaler,mmerrill3/autoscaler