Currently the error reporting of the oc node-image create command is pretty rough, as it prints out in the console the log traces captured from the node-joiner pod standard output. Even though this could help the user in understanding the problem, a lot of many unnecessary technical details are exposed, making the overall experience cumbersome.

For this reasons, node-joiner tool should generate a proper json file with the outcome of the action, including all the error messages eventually found.
The oc command should fetch such json output and report it in the console, instead of the showing up the node-joiner pod logs output.

Use also a flag to report the full pod logs, in case of troubleshooting
Manage the backward compatibility with the older version of node-joiner that does not support the enhanced output