Abstract deployment manifest retrieval from user config

- All commands now print the deployment manifest path & check that it
  exists

[#83523544]

Signed-off-by: Karl Isenberg <kisenberg@pivotal.io>
Print deployment state path along with deployment manifest path

- Standardized deployment state/manifest output syntax to be more declarative

[#83523544]

Signed-off-by: Karl Isenberg <kisenberg@pivotal.io>