UPDATE 3-TransCanada ramps up East Coast pipeline plan as Keystone stalls

By Scott Haggett CALGARY, Alberta, Aug 1 (Reuters) - TransCanada Corp on Thursday said it would move ahead with Canada's largest-ever pipeline, expanding the scale of its $12 billion plan to ship oil sands crude in the West to refiners on its east coast and beyond as its U.S.-bound Keystone XL line stalls in Washington. Canada's No. 2 pipeline company said "strong market support" convinced it to build the 1.1-million-barrel-per-day Energy East Pipeline, which will stretch 2,700 miles(4,