Pause and Resume API Support

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Expected Customer Behavior

1. User can pause ccr anytime after bootstrap is done and shards start following the leader shard .
2. User can hit resume ccr anytime once after pause .
3. Resume anytime on an unpaused index will throw error.
4. Subsequent resume operation can fail in case it is done too late after pause . It will result in replication task getting failed.
5. Between pause-resume, the newer operations should not be replicated .
6. CCR Plugin will pause for non-retriable errors. For retriable errors,we will infinitely retry.
7. We will store the reason of the Pause : whether it is customer driven via API or due to a failed resumable task . .