(Adds details about Digital Asset in par 10, updates share movement) Dec 7 (Reuters) - Australia's ASX Ltd said on Thursday it would replace its registry, settlement and clearing system with blockchain technology to cut costs for customers. The decision to replace the Clearing House Electronic Subregister System (CHESS) on Australia's main bourse follows two years of testing of distributed ledger technology, also known as blockchain. "We believe that using DLT to replace CHESS will enable our...