The crazed transgender dad who shot up a high school hockey game in Rhode Island threatened to go “BERSERK” in a trans-rights rant just a day before he massacred two family members and injured three others. Robert Dorgan, who also identified as Roberta Esposito, killed himself after opening fire at the Pawtucket ice rink where his son was playing on Monday afternoon — less than a week after another transgender gunman shot up a school in one of Canada’s deadliest mass shootings. The night before the bloodshed, the 56-year-old dad — who underwent gender reassignment surgery in 2020 — made...