“More jokes!” After D.C. and Warner Bros’ ultra-sombre film debuts left them with box office egg on their faces, the cinematic DCU has been itching, ever gradually, closer to the light, well-received populism of the Marvel house style. Justice League’s most human moment was a Josh Whedon gag; Wonder Woman swung for idealism and fish-out-of-water larks; the trailer for James Wan’s Aquaman suggests a dopey beef-bro underwater odyssey, while Shazam!‘s leans hard on the comedy, and seems to work. The memo’s gone out: the sillier the better. By that metric, Teen Titans Go! To The Movies is D.C.’s best film yet.…