Students awoke to what they thought was the murmur of children playing. They awoke to what they assumed was a pesky classmate banging on the door to borrow a textbook. They awoke from a lifelike dream that they were at a barbecue, could even smell the smoke. There was smoke. It was just after 4 in the morning. The dorm was on fire.  It had ignited in the basement lounge of the Cornell Heights Residential Club, a repurposed motel on the northern fringe of the expansive Cornell University campus in Ithaca, N.Y.