Provide a CLI method to print nicks

[ehelms]

I am a heavy user of the nicks feature within the broker_settings.yaml file. I am prone to forgetting the names of each and then have to cat ~/.config/broker/broker_settings.yaml to remind myself. I would find it useful to be able to print these nick names from the CLI.

[JacobCallahan]

@ehelms would you just want a list of nicks or their fields as well?
Maybe it would make more sense to roll this into a larger feature allowing users to view/modify sections of their config.

[ehelms]

I use descriptive enough nicks that I do not need to see their properties. Simply the list of nicks would be fine. For example, I have the following:

  rhel8
  rhel9
  stream
  streamcap
  sat616
  sat615
  sat614
  sat613
  sat612
  sat611
  cap615

[JacobCallahan]

This will be delivered in 0.6