Automatic merge from submit-queue (batch tested with PRs 42379, 42668, 42876, 41473, 43260)
Silence error messages from the docker rmi call we expect to fail
**What this PR does / why we need it**: when we removed `docker tag -f` in #34361 we added a bunch of `docker rmi` calls to preserve behavior for older docker versions. That step is usually a no-op, however, and results in confusing messages like
```
Tagging docker image gcr.io/google_containers/kube-proxy:c8d0b2e7a06b451117a8ac58fc3bb3d3 as gcr.io/kubernetes-release-test/kube-proxy-amd64:v1.5.4
Error response from daemon: No such image: gcr.io/kubernetes-release-test/kube-proxy-amd64:v1.5.4
```
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes#42665
**Special notes for your reviewer**: I could probably remove the `docker rmi` calls entirely, though I don't know if folks are still using docker < 1.10. (I think Jenkins still has 1.9.1.)
**Release note**:
```release-note
NONE
```
cc @jessfraz
Automatic merge from submit-queue
fix sed command run failed on mac os
bash command ```sed -i ... ``` run failed on mac os, it should be ```sed -i.back ..```
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>
