By Guglielmo Mangiapane and Roberto Mignucci CANAZEI, Italy (Reuters) -Eight of the people missing after the deadly collapse of part of a mountain glacier have been safely located, Italian media reported on Tuesday, bringing some relief for rescue teams searching for survivors. At least seven people were killed in the avalanche on Sunday on the Marmolada, which at more than 3,300 metres (10,830 ft) is the highest peak in the Dolomites, a range in the eastern Italian Alps straddling the regions of Trento and Veneto. “When we arrived we saw a disaster, we realised the dimensions of this enormous…