COOPR-550: Admin and Cluster CLI commands integration tests

actually, getObjectFromOutput uses a gson instance without any of our codecs, so any object that has custom deserialization logic (like ClusterDetails) will not deserialize correctly.  Is the CLI also not using our codecs to output?  If not that needs to be fixed, otherwise the CLI will output something different than the rest APIs, and you won't be able to deserialize correctly here.