Allow to schedule a node as kubernetes job.

[giorgiozoppi]

In the DAG asynchronously we're creating a monolith structure when n the Distributed ETL use case it will be nice to have a flag to distribute the node of a graph as job, doing effectively a pipeline effect using redis queuing mechanism. Suppose we have a DAG:

1. A -> B ->C
2. The user trigger the dag from A,
3. the triggering event schedule 3 types jobs A, B, C to be executed in the kubernetes cluster wherease each job type has a cardinality (number of pods associated)

This needs to be evalutated in design meeting and follow up discussion and check what currentely kubeflow does.