Add pretty printing of node group fields

Change-Id: Iff160e597805b01d4ab1172edc123cf38a87641b
Clean up printing of image details

The metadata is represented elsewhere and is not formatted well, skip
it

Change-Id: I881a35985862ebbc99128528ca032c0ca993264f
Clean up versions display in plugins-show

Change-Id: I7c9a0a19a8f1ce538c7e4df8522df8b4292c51fa
Merge "Add pretty printing of node group fields"
Merge "Clean up printing of image details"
Merge "Clean up versions display in plugins-show"