A Randomized, Double-Blind, Placebo-Controlled, Parallel-Design, Multiple-Site Study to Evaluate the Therapeutic Equivalence of Estradiol Vaginal Inserts 4 mcg (Teva Pharmaceuticals, Inc.) with IMVEXXY® (estradiol vaginal inserts) (TherapeuticsMD, Inc.) in the Treatment of Dyspareunia in Women with Vulvar and Vaginal Atrophy