You can’t miss the whiff as you drive along the 10 freeway heading to or from Arizona, a strange and horrifying stench, the Salton Sea. Chris Metzler–who visited us last year with “Everyday Sunshine: The Story of Fishbone”–co-directed “Plagues and Pleasures on the Salton Sea, an occasionally whimsical and deeply sad look at a man-made lake; the hopes, dreams and disasters that sprung from it; and the people who try to stay afloat on its shores.