Remove legacy Dockerfile [master]

[odyssey4me]

Some time ago there was an attempt done to have RPC-O use Jenkinsfile.
This attempt was aborted, but there are remaining bits which were never
cleaned up. To reduce confusion we should clean up the previous attempt.

Issue: RE-2073

[rpc-jenkins-svc]

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[odyssey4me]

2019-02-27T10:59:06+0000 ansible-lint runtests: commands[4] | bash -c /var/lib/jenkins/workspace/PR_rpc-openstack-master-container-ansible-lint-tox-test/rpc-openstack/tests/common/test-ansible-lint.sh
2019-02-27T10:59:06+0000 TEST_PLAYBOOK: /var/lib/jenkins/workspace/PR_rpc-openstack-master-container-ansible-lint-tox-test/rpc-openstack/tests/test.yml
2019-02-27T10:59:06+0000 ANSIBLE_LINT_PARAMS: 
2019-02-27T10:59:06+0000 sed: can't read /var/lib/jenkins/workspace/PR_rpc-openstack-master-container-ansible-lint-tox-test/rpc-openstack/.gitreview: No such file or directory
2019-02-27T10:59:06+0000 awk: cannot open /var/lib/jenkins/workspace/PR_rpc-openstack-master-container-ansible-lint-tox-test/rpc-openstack/.gitreview (No such file or directory)
2019-02-27T10:59:06+0000 ERROR: InvocationError for command '/bin/bash -c /var/lib/jenkins/workspace/PR_rpc-openstack-master-container-ansible-lint-tox-test/rpc-openstack/tests/common/test-ansible-lint.sh' (exited with code 2)
2019-02-27T10:59:06+0000 ___________________________________ summary ____________________________________
2019-02-27T10:59:06+0000 ERROR:   ansible-lint: commands failed

[odyssey4me]

2019-02-27T10:58:16+0000 ansible-syntax runtests: commands[4] | bash -c /var/lib/jenkins/workspace/PR_rpc-openstack-master-container-ansible-syntax-tox-test/rpc-openstack/tests/common/test-ansible-syntax.sh
2019-02-27T10:58:16+0000 sed: can't read /var/lib/jenkins/workspace/PR_rpc-openstack-master-container-ansible-syntax-tox-test/rpc-openstack/.gitreview: No such file or directory
2019-02-27T10:58:16+0000 awk: cannot open /var/lib/jenkins/workspace/PR_rpc-openstack-master-container-ansible-syntax-tox-test/rpc-openstack/.gitreview (No such file or directory)
2019-02-27T10:58:16+0000 ERROR: InvocationError for command '/bin/bash -c /var/lib/jenkins/workspace/PR_rpc-openstack-master-container-ansible-syntax-tox-test/rpc-openstack/tests/common/test-ansible-syntax.sh' (exited with code 2)
2019-02-27T10:58:16+0000 ___________________________________ summary ____________________________________
2019-02-27T10:58:16+0000 ERROR:   ansible-syntax: commands failed

[odyssey4me]

Until #3509 merges, the syntax/lint tests will fail.

[odyssey4me]

recheck_all

[odyssey4me]

recheck_container_ansible-lint_tox-test
recheck_container_ansible-syntax_tox-test
recheck_bionic_no_artifacts_swift_deploy

[odyssey4me]

recheck_bionic_no_artifacts_swift_deploy