imaging changes for casa_envoy and vela

...li/executables/pexable/casa_envoy/casa_envoy/launchers.py

.../cli/executables/pexable/casa_envoy/casa_envoy/palaver.py

.../cli/executables/pexable/casa_envoy/test/cmsimage-PPR.xml

...i/executables/pexable/casa_envoy/test/image-metadata.json

...li/executables/pexable/casa_envoy/test/test_casa_envoy.py

...cli/executables/pexable/casa_envoy/test/test_launchers.py

apps/cli/executables/pexable/vela/test/cmsimage-PPR.xml

apps/cli/executables/pexable/vela/test/image-metadata.json

apps/cli/executables/pexable/vela/test/test_emulators.py

apps/cli/executables/pexable/vela/test/test_forger.py

apps/cli/executables/pexable/vela/test/test_vela.py

apps/cli/executables/pexable/vela/vela/emulators.py

apps/cli/executables/pexable/vela/vela/forger.py

apps/cli/executables/pexable/vela/vela/interfaces.py

apps/cli/executables/pexable/vela/vela/quasar.py

...rkspaces/workspaces/workflow/services/workflow_service.py