Feast integration

[sarahwooders]

Write updates (inserts/deletes) into the Feast online and offline stores.

This could potentially be implemented by reading the providers in the Feast config file and writing to them directly. e.g.

from ralf import Ralf, FeastConnector 

ralf = Ralf()
connector = FeastConnector(config="feature_store.yaml") # read providers and connect

[narang-amit]

Should the same table be allowed to have multiple connectors? e.g. one table should be stored in Feast and in Redis or something?

[simon-mo]

Should the same table be allowed to have multiple connectors?

This but it should be implemented in a layer above. Something like:

connector = MultiplexingConnect([FeastConnector(), RedisConnector()])

[narang-amit]

Why that approach over TableState(schema, List[Connector])? @simon-mo

[simon-mo]

Abstractions. Now table only cares about writing to a single connector and it's kept simple.