Global inflation appears tamer than many had thought it would be by now, still held back by a modest outlook for economic growth, meaning central banks look likely to leave rates lower for longer — or even ease policy further. For those watching the world economy, China, not Greece, has for a while remained the number one concern. The panic by the Chinese authorities last week as they went through tool after tool to halt the stock market’s fall after a massive boom suggests serious concern about damage to a slowing economy that is generating just 1.4 percent inflation.