Adding retry logic for SDC Client in Distribution

Adding retry logic for SDC Client in Distribution

* SdcReceptionHandler in distribution tries to initialize & start the
SDC Client when distribution framework comes up. If by any chance the
SDC service is not up then currently the SdcReceptionHandler throws an
exception to the distribution activator and the distribution framework
goes down. And the health check fails.

* This review fixes it by adding a retry mechanism in
SdcReceptionHandler for all lifecycle methods of SdcClient (init, start,
stop). After failure the same operation is retried again with some
delay. The delay is passed as parameter from configuration json file.
The minimum default value for the delay is kept as 30 seconds.

* Adding SdcClientHandler timer task for performing the retries
asynchronously.

Change-Id: Ibb6d936fcf4872c82f87e2cd04a00583b81c92ff
Issue-ID: POLICY-1035
Signed-off-by: ramverma <ram.krishna.verma@ericsson.com>