NewBlocksProvider constructor function to create blocks deliverer instance.

BlocksDeliverer defines interface which actually helps to abstract the AtomicBroadcast_DeliverClient with only required method for blocks provider.

BlocksProvider used to read blocks from the ordering service for specified chain it subscribed to.

GossipServiceAdapter serves to provide basic functionality required from gossip service by delivery service.

LedgerInfo an adapter to provide the interface to query the ledger committer for current ledger height.