Use Options to configure DataAvailabilityLayerClient

[gupadhyaya]

Currently, the Init api of DataAvailabilityLayerClient takes a couple of types.NamespaceID and config as []byte.

Init(headerNamespaceID, dataNamespaceID types.NamespaceID, config []byte, kvStore ds.Datastore, logger log.Logger) error

but, we should move to using Options for such configurations.