It's getting pretty wild in the beverage aisle these days — from the rainbow wall of seltzers, to the increasingly strange flavors of Pepsi, to the new "functional" sodas with added fiber or supplements that supposedly offer health benefits. Where are all these new drinks coming from? And why does it seem like the options are multiplying faster than ever?Today on the show, we go behind the scenes at one of the nation’s top-secret beverage labora…