Awful dependency problem caused by romulus

[David Cheney]

Hello,

github.com/juju/juju/cmd/juju/commands:
  github.com/juju/romulus/cmd/commands:
    github.com/juju/romulus/cmd/setplan: <<<<<<<<<<<<<<<<<<<<<
      github.com/juju/juju/api/service:
      github.com/juju/juju/cmd/modelcmd:

cmd/juju depends on the romulus repository, and the romulus repository
depends on juju.

This is terrible. It means we _cannot_ change the public api of the
juju that romulus depends on because then juju won't compile, and we
cannot land the fix to romulus without breaking juju.

Casey, please fix this immediately. Either juju depends on romulus, or
romulus depends on juju, but at the moment they both depend on each
other and that is a showstopper,

Thanks

Dave