And so ends the Eli Manning era. A shocking news release from the Giants at around 3:30 p.m. Tuesday announced that Manning won’t be their starting quarterback for the first time since 2004. At 2-9, second-year coach Ben McAdoo — who soon might be ex-coach Ben McAdoo — has decided Manning is no longer in the team’s plans and that Geno Smith will get a shot Sunday against the Raiders in Oakland. The Giants also want to get a look at rookie quarterback Davis Webb, so he, too, will figure into the mix as the Giants lurch toward the finish line of a lost season.