U.S. stock futures were a touch lower on Friday, at the end of a week in which stocks have struggled for direction amid uncertainty about the ongoing government shutdown.Futures tracking the Dow Jones Industrial Average were up just 10 points, effectively trading flat. S&P 500 futures fell 0.1%, and contracts tied to the tech-heavy Nasdaq 100 were down by the same amount.The yield on the 10-year U.S. Treasury note was down 3 basis points to 4.11%. The dollar slipped 0.2% against a weighted basket of its pee ...