PHILADELPHIA – Grades are handed out immediately after each day of the draft from experts and non-experts alike. Winners and losers are anointed. Typically, it takes three years to judge a class. At least that’s the length of time it takes me to hand out the Eagles’ draft class grades. This one, though, looks like an early ‘A.’ It’s been an impressive haul for them, landing both the Biletnikoff Award winner for the nation’s best receiver in Makai Lemon in round one, and the John Mackey Award winner for the country’s best tight end in Eli Stowers in round two. Those two pass catchers will be fixtures on the offense for years to come. In the third round, the Eagles took a massive offensive tackle in Markell Bell, who did not allow a single snap last year on a University of Miami team that played for the national title. Those were just the draft picks. There’s more. “I think you gotta put (Jonathan) Greenard into this draft,” said general manager Howie Roseman on Friday night before the third round ended.…