“Crush” is a formulaic high school rom-com with one great big out and over-powering gay twist. Who better to pass along “glow in the dark dental dams” and toothbrush-as-vibrator advice? Well, if Harvey Fierstein isn’t available? How gay? They cast Megan Mullally as the kid’s indulgent, supportive and overly “helpful” mother. With “Crush,” Hulu serves up the gayest gay vulgarian heroine in a gay fantasia of a high school ever…since “Glee!” anyway. Boy, if Disney really wants to get Wuhan Ron’s “Don’t Say Gay” Goat, they should buy him a subscription to Hulu.