A gender wars back-and-forth with surprising emotional richness, Little Miss Sunshine directors Jonathan Dayton and Valerie Faris serve up an ace with Battle of the Sexes, a warm, solidly entertaining look at the 1973 tennis match between Billie Jean King, the top-ranked female player, and Bobby Riggs, an ex-World Champion hungry for the spotlight. Some of Little Miss Sunshine’s affection for misfits united by shared dysfunction is visible in Battle of the Sexes, Simon Beaufoy’s script framing Billie Jean (Emma Stone) and Bobby (Steve Carell) as a pair of almost-weirdos comparable in their compulsions. Billie Jean’s rebellion against tennis establishment…