Amid some mixed sentiment, framing lumber prices increased last week in U.S. Weather clouded the views of traders in some markets.   But with warm temperatures across the East and a sense that the remainder of winter held little threat going forward, buyers stepped up purchases. Trading was especially active early on, as momentum from the previous week’s surge carried over through Tuesday. Activity eased at the mill level, as producers extended order files and raised prices — in some cases sharply.     This Week Mar 11 Last Week Mar 4 ...