DENVER — The Mets returned to game action following a snowout to split a doubleheader in the Mile High City. The Mets beat the Rockies, 5-1, in Game 1 of a doubleheader at Coors Field on Saturday behind 5 1/3 solid innings from Carlos Carrasco and an early outburst from the offense. The Mets matched their season-high three-game winning streak by taking the first game of the twin bill. But they badly lost the nightcap following volatile pitching performances in an 11-3 blowout to Colorado in Game 2. Carrasco, in his Coors Field debut, lowered his season ERA to 3.50 after his 87-pitch effort tha…