[INFINITY-1539] create service account on dcos18 (#997)
[INFINITY-1539] create service account on dcos18 (#997)

* Fail on service account creation failure.
* Use older enterprise cli extension to work with older cli.
vishnu2kmohan/dcos-commons,mesosphere/dcos-commons,vishnu2kmohan/dcos-commons,vishnu2kmohan/dcos-commons,vishnu2kmohan/dcos-commons,mesosphere/dcos-commons,mesosphere/dcos-commons,vishnu2kmohan/dcos-commons,mesosphere/dcos-commons,mesosphere/dcos-commons