Added Jenkinsfile to orchestrate multibranch pipeline build on Jenkins.
Added Jenkinsfile to orchestrate multibranch pipeline build on Jenkins.

mesosphere/dcos-cli,kensipe/dcos-cli,kensipe/dcos-cli,mesosphere/dcos-cli,dcos/dcos-cli,kensipe/dcos-cli,dcos/dcos-cli,kensipe/dcos-cli,kensipe/dcos-cli,dcos/dcos-cli,dcos/dcos-cli,dcos/dcos-cli,mesosphere/dcos-cli