Las Vegas cops busted a transgender gunman who allegedly planned a casino massacre using a huge cache of weapons. Allison Howlett, 36, who was born a man but lives as a woman, was arrested Saturday on charges of making terroristic threats, assault with a deadly weapon, auto theft, gun theft and other offenses. The wild story unfolded shortly after 9:30 a.m. Saturday when Howlett’s former spouse, who is female, called police to report Howlett had stolen her car and the vehicle held numerous firearms, Henderson Police Chief Reggie Rader said. The former spouse said Howlett intended to commit “suicide by...