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>.
Update bazelbuild/rules_go, kubernetes/repo-infra, and gazelle dependencies
**What this PR does / why we need it**: updates our bazelbuild/rules_go dependency in order to bump everything to go1.9.4. I'm separating this effort into two separate PRs, since updating rules_go requires a large cleanup, removing an attribute from most build rules.
**Release note**:
```release-note
NONE
```
Kubernetes-commit: 96ec3187180b9c1d722756b3ea0984ebe65424dc
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>.
Bump rules_go and build "static" binaries in pure Go mode
**What this PR does / why we need it**: uses latest set of enhancements in bazelbuild/rules_go to properly build the "static" Go binaries using pure Go (i.e. `CGO_ENABLED=0`), and to support cross compilation of these binaries. Cross compilation of cgo-enabled binaries is still not supported.
Also depends on https://github.com/kubernetes/repo-infra/pull/52, and requires bazel 0.8+ (which is not yet enabled in CI for kubernetes/kubernetes).
Note that for proper cross compilation we'll also need to remove the hardcoded "linux-amd64" that's strewn about several `BUILD` files.
**Release note**:
```release-note
NONE
```
/hold
/assign @BenTheElder @mikedanese @spxtr
Kubernetes-commit: f5f6f3e715cb8dfbd9657a4229c77ec6a5eab135
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>.
Introduce new `VolumeAttachment` API Object
**What this PR does / why we need it**:
Introduce a new `VolumeAttachment` API Object. This object will be used by the CSI volume plugin to enable external attachers (see design [here](https://github.com/kubernetes/community/pull/1258). In the future, existing volume plugins can be refactored to use this object as well.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: Part of issue https://github.com/kubernetes/features/issues/178
**Special notes for your reviewer**:
None
**Release note**:
```release-note
NONE
```
Kubernetes-commit: ebe8ea73fd1a961779242dfbb629befa153e96fc
Automatic merge from submit-queue (batch tested with PRs 55004, 54957). 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>.
Update kube-openapi to use validation
**What this PR does / why we need it**: Moves openapi validation code to kube-openapi, so that we can move the rest of the code to apimachinery repository, so that later we can use it from both the client and the server.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #Nothing
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
Kubernetes-commit: 55e216f56eac0082acc6be655d9ae09cf9ba38a8
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>.
sample-controller: add example CRD controller
**What this PR does / why we need it**:
Adds a sample-controller example repository
fixes#52752
**Special notes for your reviewer**:
This is currently based on the sttts:sttts-codegen-scripts branch and should not be merged until that is (ref https://github.com/kubernetes/kubernetes/pull/52186)
**Release note**:
```
Add sample-controller repository
```
/cc @sttts @nikhita @colemickens
Kubernetes-commit: 9a7800f7d2efb88b397674672ac56f898826cf7c
