Review command outputs

[glooms]

We should consider looking over what is returned our commands as well.
Currently I would argue it is too terse. For example:

> corectl dimension rm my-dim
Saving app... Done

Maybe we would like to return the name or id for the removed dimension or something like that.
Furthermore, I think that while working with an app, it is implied that the changes you are making are saved if nothing else is specified.

Originally posted by @glooms in #342 (comment)