Representations of the Ripple, Bitcoin, Etherum and Litecoin virtual currencies are seen on a PC motherboard in this illustration picture, February 13, 2018. REUTERS/Dado Ruvic/Illustration NEW YORK (Reuters Breakingviews) - After all the hype, blockchain is due for a breakthrough in 2019. Banks and companies are gradually applying versions of the distributed-ledger technology associated with bitcoin to tasks like settlement. Demonstrating blockchain’s utility, though, will say little about...