The head of the union representing 4,000 New York State Police Troopers – a workforce overseen by Democratic Gov. Andrew Cuomo — is backing Republican President Trump’s re-election bid. “Donald Trump has our back. President Trump has supported us when so many people have turned against us,” NYS Troopers PBA president Thomas Mungeer told the Post on the eve of the Republican National Convention. “Joe Biden supported cops in the past but he’s turned his back on us,” said Mungeer, referring to the former vice president and Democratic presidential nominee who is taking on Trump in the Nov. 3 general...