By David Flaherty At 8 pm, amidst the sweltering steam bath of NYC, the Half Moon set sail on the East River. Aboard were 27 cases of German Riesling, 2 kegs of Gotham Project Riesling, about 40 tons of ice, 3 local bands, 1 German wine queen and 225 thirsty acidhounds. The Summer of Riesling sold-out boat cruise was underway. Stepping aboard, the guests were greeted with a glass of Gotham Project Riesling from upstate NY in the Finger Lakes.  From here on out, it was all German Riesling as the month of July has been devoted to the motherland.…