The Van Leeuwen Artisan ice cream truck rolled up to DUMBO for a couple hours this afternoon, affording Gothamist a taste of creamy ecstasy. And not a moment too soon; driver Dan Suarez told us that a turf war had already broken out on Main Street with rival truck Tommy’s Ice Cream, whose owner told Dan he’s been working the block for four years. One could see why Tommy would be threatened: there was an......