In a crossover crazy world Cadillac certainly hasn’t given shoppers many reasons to visit one of their showrooms. But perhaps it was worth the wait. This is the first ever XT4.From subcompact to gargantuan, automakers’ SUV lineups are growing in every direction. But until now, Cadillac’s offerings have started at the midsize XT5 and jumped from there right to the big boy Escalade. So in comes the XT4, compact-sized and …