With the opening of their current production, Stephen Sondheim's "Merrily We Roll Along,” New Helvetia Theatre makes a big jump in its growth as a theater company. The barely 3-year-old company, under founder Connor Mickiewicz, has brought Sacramento audiences wonderful contemporary musical theater productions that, for one reason or another, would not otherwise be produced here. But taking on a play like "Merrily We Roll Along," by such a master as Sondheim, required a great deal of growth in almost every area for New Helvetia. I am happy to report that it has all come together and that their production is a critical success and should be a very rewarding experience for its viewers. The