job name supports underline

[Yancey1989]

Error message:

$ paddlecloud submit -jobname fit_a_line -cpu 1 -gpu 1 -parallelism 1 -entry "python train.py" fit_a_line/
uploading: fit_a_line/train.py...
error submiting job: (422)
Reason: Unprocessable Entity
HTTP response headers: HTTPHeaderDict({'Date': 'Thu, 06 Jul 2017 07:52:39 GMT', 'Content-Length': '1729', 'Content-Type': 'application/json'})
HTTP response body: {
  "kind": "Status",
  "apiVersion": "v1",
  "metadata": {},
  "status": "Failure",
  "message": "ReplicaSet.extensions \"fit_a_line-pserver\" is invalid: [metadata.name: Invalid value: \"fit_a_line-pserver\": a DNS-1123 subdomain must consist of lowe\
r case alphanumeric characters, '-' or '.', and must start and end with an alphanumeric character (e.g. 'example.com', regex used for validation is '[a-z0-9]([-a-z0-9]\
*[a-z0-9])?(\\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*'), spec.template.spec.containers[0].name: Invalid value: \"fit_a_line\": a DNS-1123 label must consist of lower case alp\
hanumeric characters or '-', and must start and end with an alphanumeric character (e.g. 'my-name',  or '123-abc', regex used for validation is '[a-z0-9]([-a-z0-9]*[a-\
z0-9])?')]",
  "reason": "Invalid",
  "details": {
    "name": "fit_a_line-pserver",
    "group": "extensions",
    "kind": "ReplicaSet",
    "causes": [
      {
        "reason": "FieldValueInvalid",
        "message": "Invalid value: \"fit_a_line-pserver\": a DNS-1123 subdomain must consist of lower case alphanumeric characters, '-' or '.', and must start and end \
with an alphanumeric character (e.g. 'example.com', regex used for validation is '[a-z0-9]([-a-z0-9]*[a-z0-9])?(\\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*')",
        "field": "metadata.name"
      },
      {
        "reason": "FieldValueInvalid",
        "message": "Invalid value: \"fit_a_line\": a DNS-1123 label must consist of lower case alphanumeric characters or '-', and must start and end with an alphanume\
ric character (e.g. 'my-name',  or '123-abc', regex used for validation is '[a-z0-9]([-a-z0-9]*[a-z0-9])?')",
        "field": "spec.template.spec.containers[0].name"
      }
    ]
  },
  "code": 422
}

Kubernetes does allow to use underline as the metadata.name, maybe paddlecloud would do some escaping to solve this problem.

[Yancey1989]

Escaping the job name may cause some other problems, such as the same job name... so we can check the job name with paddlecloud client side.