It's all in the hops, said O'Brian Tomalin. Well, some of it's in the timing. Tomalin, 47, was showing off his new BLDG8 Brewing brewery in the Cutlery Building on Riverside Drive, one of two recently opened breweries in Florence. Factor in the new Pie Bar and the Birds Block-like building at 100 Main St., and Florence is the hip new spot in Northampton. BLDG8 Brewing, Tomalin's business, opened about three weeks ago. Unlike Brew Practitioners on Main Street, BLDG8 has no pub. It just makes beer. Good beer.