Let history remember when Alvin Bragg went soft on snowball-throwing Diaper Man and essentially endorsed the disrespect of the men and women in blue. Our prosecution-averse Manhattan DA dropped the police-assault charges against Gusmane Coulibaly, who goes by Diaper Man on YouTube where he posts idiotic videos of himself interviewing couples about their trust levels and him brushing his face with a toothbrush. Scintillating stuff. Coulibaly, 27, who was arrested earlier this month for attempted