For single entrepreneurs, the dating game offers unique challenges. The long hours, obsession with work and unpredictable lifestyle are all factors that can interfere. But in early tests, the site seemed to have trouble determining what’s local. Seattle Times’ reporter Joe O’Sullivan. Craigslist cut out classified sections. Online. Just two days after his arrest, John Charlton has been charged for the alleged murder of Seattle area nurse Ingrid Lyne, But…