Docker cleanup fails on created containers

[dfaller]

The Docker cleanup tasks fail when containers are created, but fail before they start running. Scale never receives a TASK_RUNNING update from Mesos, which means that Scale never gets the container name in order to delete it. Since the container doesn't get deleted, the volumes can't be deleted.

In order to fix this, the cleanup task needs to (before cleaning up volumes) look through containers in the created state, inspect them for the Scale framework ID, and delete them.