TOKYO (Reuters) -A leading indicator of Japan's service-sector inflation perked up in August, data showed on Thursday, backing up the central bank's view that rising labour costs will help keep inflation sustainably around its 2% target. The services producer price index, which tracks the price companies charge each other for services, rose 2.7% in August from a year earlier, Bank of Japan data showed, accelerating from a revised 2.6% gain in July. Hotel prices rose 7.6% year-on-year in August, acceler ...