Scaleup UI polish.
Display constraints correctly in summary panel.
Merge pull request #436 from huwshimi/scaleup-polish

Scaleup UI polish

This branch fixes the scale up button colour and sets the unit count from the model.
Merge pull request #433 from huwshimi/fix-blank-constraints-message

Display constraints correctly in summary panel

If the constraints are set to null then we should display the correct message. See: https://bugs.launchpad.net/juju-gui/+bug/1339782
Remove uncommitted units when the ghost service is removed.
Merge pull request #435 from jaycee/clear-unplaced-unit

Remove uncommitted units when the ghost service is removed.

`_destroyQueuedService` attempts to remove all the items associated with the queued ("ghost") service. While it gets the entries for adding the uncommitted units, it doesn't remove the actual units.

This branch remedies that, and updates the test showing it removes queued service to demonstrate it also removes uncommited units.