Provide the possibility to add a timeout for a deployment, where it would kill the deployment and rollback the app to the previous deployment if it deployment wasn't finished within the given time.
There are two use cases, where it would be useful:
1. you request more resources than are available in the cluster
2. you request more resources than will become available in a reasonable amount of time
This is to avoid getting an app stuck in a deployment process (Marathon keeps trying to scale the app).