Residential solar installer SunPower (NASDAQ:SPWR) is flailing today. Shares of SPWR stock have plunged more than 50% in early afternoon trading, after the company announced plans to halt new leases, installations and shipments to customers.This move is a continuation of the longer-term trend we’ve seen with this company. Other competitors in the space appear to be getting hit by many of the same headwinds. But on this move, Guggenheim analysts suggested that the end may be near for SunPower, as the company ...