Automatic merge from submit-queue (batch tested with PRs 50602, 51561, 51703, 51748, 49142)
Use arm32v7|arm64v8 images instead of the deprecated armhf|aarch64 image organizations
**What this PR does / why we need it**:
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes#50601
**Special notes for your reviewer**:
/assign @ixdy @jbeda @zmerlynn
**Release note**:
```release-note
Use arm32v7|arm64v8 images instead of the deprecated armhf|aarch64 image organizations
```
Automatic merge from submit-queue (batch tested with PRs 41104, 41245, 40722, 41439, 41502)
Change the etcd rollback tool to do rollback to 2.2.1 version.
I did some tests of it and for my 3-node cluster with 1 deployment it worked fine.
But before merging this, we should probably do way more testing (we should rerun tests that @mml was doing for the previous script).
@lavalamp @xiang90
Automatic merge from submit-queue
Remove all MAINTAINER statements in the codebase as they are deprecated
**What this PR does / why we need it**:
ref: https://github.com/docker/docker/pull/25466
**Release note**:
```release-note
Remove all MAINTAINER statements in Dockerfiles in the codebase as they are deprecated by docker
```
@ixdy @thockin (who else should be notified?)
Automatic merge from submit-queue
Update `gcloud docker` commands to use `gcloud docker -- ARGS`
We can then avoid the following warning:
```
WARNING: The '--' argument must be specified between gcloud specific args on the left and DOCKER_ARGS on the right. IMPORTANT: previously, commands allowed the omission of the --, and unparsed arguments were treated as implementation args. This usage is being deprecated and will be removed in March 2017.
This will be strictly enforced in March 2017. Use 'gcloud beta docker' to see new behavior.
```
We can then avoid the following warning:
```
WARNING: The '--' argument must be specified between gcloud specific args on the left and DOCKER_ARGS on the right. IMPORTANT: previously, commands allowed the omission of the --, and unparsed arguments were treated as implementation args. This usage is being deprecated and will be removed in March 2017.
This will be strictly enforced in March 2017. Use 'gcloud beta docker' to see new behavior.
```
Signed-off-by: Jess Frazelle <acidburn@google.com>
