Executor: delete pod when tasksetup fail

[alessandro-sorint]

What would you like to be added: We would like to add automatic deleting of the pod when the task setup fail

Why is this needed: when for example the init container don't find the image, or we have reached the docker rate limits, the pod init fail(and fail the task) but the pod is not deleted; it remain in ImagePullBackOff status

[alessandro-sorint]

My idea is to add a status field in the Pod interface.
I think we have to convert the k8s/docker status in an agola type string, I investigate what status value return k8s and docker driver.
Using the podsCleaner routine we can delete the pod if the status is "failed"