rhondawinter/FlickrSexy Soup Lady at the summer's first Bike-In Movie Night.Remember the classic Rockestra of the '70s? A couple dozen gods of rock, standing side by side on a stadium stage, simultaneously laying down hellaciously tasty chords? Well, the cart food equivalent drops tonight, when a pantheon of local food vendors converges on S.F. Bicycle Coalition's Bike-In Movie Night in a parking lot opposite the Good Hotel (112 Seventh St. at Mission) for the third such event of the summ