Currently we have a target unset command while other commands (env) have a -u flag to do the unset.
We should align this.
Moreover, the target unset command currently has no subcommands but uses the target kind as argument. This is also not consistent.

I vote for introducing an unset flag for this command, too. We could deprecate the unset command and eventually remove it. Or, if we change it bevor the initial release we could also think about removing it immediately.