remove kubernetes related option

[zouyee]

Signed-off-by: Zou Nengren [email protected]

notes for reviewer:

Also re-enabled and adjusted the kubernetes upstream behavior test to verify default upstream 
behavior. The test had been commented out when the upstream option was originally deprecated.

coredns/coredns#3737

[zouyee]

/cc @miekg

[miekg]

'ci' is pulled down from circle-ci to test, are we sure this works? @chrisohaver

[chrisohaver]

Looks ok. However, there is more that is being changed here than just the removal of upstream option, which warrants explanation. Even if it seems obvious now, it may not be to others in the future.

@zouyee, please write a description.

[zouyee]

/assign @chrisohaver

[chrisohaver]

My apologies, what I meant was to add a description to the PR here in github, not to add comments to each changed line of code.

Something like ... "Also re-enabled and adjusted the kubernetes upstream behavior test to verify default upstream behavior. The test had been commented out when the upstream option was originally deprecated."

Can you remove the comments added in 1c186d6, I don't think they are needed. Thanks!