This commit fixes a bug on the mvds library where the nextEpoch would be
incorrectly summed to the retry time, resulting in messages not being
retried, or retried much less frequently the longer the app was running.
It also updates the retry timing to backoff exponentially at multiple of
30 seconds.
Adds support for datasync, V1Messages and disabling the discovery topic.
This is a backward compatible change as long as they are not toggled on
(they are not by default).
Samuel Hawksby-Robinson
Andrea Maria Piana
Adam Babik