Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Ensure reasons end up as comments in kubectl edit.
**What this PR does / why we need it**:
This PR helps making sure that all text in the header of the file is prefixed with `#` when using `kubectl edit` to fix schema validation errors. The problem is best described with an example:
*Before:*
```yaml
# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
# mycrd "example-cr" was not valid:
# * []: Invalid value: map[string]interface {}{"apiVersion":"example.com/v1alpha1", "kind":"MyCRD", "metadata":map[string]interface {}{"clusterName":"", "creationTimestamp":"2018-03-09T16:16:41Z", "name":"example-cr", "namespace":"default", "resourceVersion":"12399", "selfLink":"", "uid":"4089f5bd-23b5-11e8-a33f-42010aa40081", "generation":0}, "spec":map[string]interface {}{"size":-1}}: validation failure list:
spec.size in body should be greater than or equal to 1
#
apiVersion: example.com/v1alpha1
kind: MyCRD
```
This obviously won't be accepted as input, the user having to manually add a `#` to the line in the header.
*After:*
```yaml
# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
# mycrd "example-cr" was not valid:
# * []: Invalid value: map[string]interface {}{"apiVersion":"example.com/v1alpha1", "kind":"MyCRD", "metadata":map[string]interface {}{"clusterName":"", "creationTimestamp":"2018-03-09T16:16:41Z", "name":"example-cr", "namespace":"default", "resourceVersion":"12399", "selfLink":"", "uid":"4089f5bd-23b5-11e8-a33f-42010aa40081", "generation":0}, "spec":map[string]interface {}{"size":-1}}: validation failure list:
# spec.size in body should be greater than or equal to 1
#
apiVersion: example.com/v1alpha1
kind: MyCRD
```
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
(None that I am aware of)
**Special notes for your reviewer**:
(None)
**Release note**:
```release-note
Ensure reasons end up as comments in `kubectl edit`.
```