Update README example for running command to new DC/OS E2E CLI
Update README example for running command to new DC/OS E2E CLI

mesosphere-mergebot/mergebot-test-dcos,mesosphere-mergebot/mergebot-test-dcos,dcos/dcos,kensipe/dcos,GoelDeepak/dcos,mesosphere-mergebot/dcos,kensipe/dcos,mesosphere-mergebot/dcos,kensipe/dcos,mesosphere-mergebot/mergebot-test-dcos,dcos/dcos,mesosphere-mergebot/mergebot-test-dcos,dcos/dcos,GoelDeepak/dcos,dcos/dcos,dcos/dcos,mesosphere-mergebot/dcos,GoelDeepak/dcos,mesosphere-mergebot/dcos,kensipe/dcos,GoelDeepak/dcos