Deep in the heart of Brooklyn, just off the Gowanus Canal, hidden behind a CubeSmart storage facility, is the colossal Powerhouse Arts building, home to the Powerhouse: International festival through December 13th. As a Brooklynite myself, I relish the chance to discover exciting, first-class work in my borough. Others might balk at the unfamiliar address, but to miss the Powerhouse: International festival would be t…