Fix NPE when getting Consul configuration

No initial value for AtomicReference was provided hence we had a little
race condition.

Retry when consul returns error.

Change-Id: Ie38ca7fbf445123e98ee94703eba501bb5233fab
Signed-off-by: Piotr Jaszczyk <piotr.jaszczyk@nokia.com>
Issue-ID: DCAEGEN2-601
5 files changed