Update Cluster Autoscaler entrypoint

[MaciekPytel]

What this PR does / why we need it:
Update Cluster Autoscaler manifest file to use new shell wrapper instead of directly calling CA binary (the wrapper is already included in current CA image).
Add params to improve logging.

Which issue this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged): fixes #

Special notes for your reviewer:

Release note:

[k8s-ci-robot]

Hi @MaciekPytel. Thanks for your PR.

I'm waiting for a kubernetes member to verify that this patch is reasonable to test. If it is, they should reply with @k8s-bot ok to test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[k8s-reviewable]

This change is 

[eparis]

/approve
@k8s-bot ok to test

[mwielgus]

/lgtm

[k8s-github-robot]

[APPROVALNOTIFIER] This PR is APPROVED

The following people have approved this PR: MaciekPytel, eparis, mwielgus

Needs approval from an approver in each of these OWNERS Files:

• cluster/OWNERS [eparis]

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[mwielgus]

@k8s-bot gce etcd3 e2e test this

[mwielgus]

@k8s-bot kops aws e2e test this

[rata]

just curious, can't this fill the container disk? What happens if this fills the disk?

[mwielgus]

This file is mounted from the machine disk. I guess that there is some log rotation policy for /var/logs on the master (but can doublecheck).