[STREAMING] SPARK-1730. Make receiver store data reliably to avoid data-loss on exec...

...utor failures.

Added a new method in Receiver, ReceiverSupervisor, ReceiverSupervisorImpl to store the data
and callback a supplied function with a given argument.
We can use  `executor.pushArrayBuffer(dataBuffer, None, None, Option(callback))`  to take care of it inside this function.