Add in-progress commit status change indicator

When deploying a changeset there is a time between when the ecs sends the command and juju ack's it. This time can be quite large on large deployments and on slow environments. This now changes the blue circle in the machine view to a yellow one until the juju ack.
I had left this empty so that it would fail spectacularly if it wasn't set :) I could add a default if you'd prefer. Also I'm not sure what the default should be...committed is probably the most common.