The cryptocurrency market could do with some respite but its convention-breaking nature means there is no hiatus. Trading in digital assets such as bitcoin and ethereum runs 24/7, unlike their conventional peers in equities on the New York and London stock exchanges, which at least get the weekend off.So one torrid week tends to run into another for this most cutting-edge of markets. Bitcoin – the cryptocurrency cornerstone – fell below the key level of $20,000 on Saturday morning, meaning it...