The greatest love story ever told, starring…garden gnomes? In “Gnomeo & Juliet,” Shakespeare’s revered tale gets a comical, off-the-wall makeover. Directed by Kelly Asbury (co-director of “Shrek 2”) and showcasing both classic and original songs by Elton John, the film features the voices of James McAvoy and Emily Blunt as Gnomeo and Juliet, who have as many obstacles to overcome as their quasi namesakes when they are caught up in a feud between neighbors. But with plastic pink flamingos and thrilling lawnmower races in the mix, can this young couple find a happy ending?