studyJob with non-kubeflow namespace cannot work

[hougangliu]

Fixes: #301

---

This change is 

[hougangliu]

Before create a non-kubeflow (saying nonkubeflow) namespace studyJob, we should doc that user must run below command:

$ cat mcrbac.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
  name: metrics-collector
  namespace: nonkubeflow
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: metrics-collector
  namespace: nonkubeflow
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: metrics-collector
subjects:
- kind: ServiceAccount
  name: metrics-collector
  namespace: nonkubeflow
$ kubeflow apply -f  mcrbac.yaml

[hougangliu]

/assign @YujiOshima @richardsliu

[richardsliu]

/lgtm
/approve

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[johnugeorge]

Why is this change added ?

[hougangliu]

kube-dns will assign k8s services a DNS A record for a name of the form my-svc.my-namespace.svc.cluster.local and my-svc.my-namespace. This resolves to the cluster IP of the Service.
vizier-core is service name, and if we don't add namespace, when Pod in non-kubeflow namespace cannot resolve vizier-core to its cluster IP (it tries to resolve vizier-core.non-kubeflow).

[johnugeorge]

Yes. I mean to say that vizier core can run in any namespace