It’s a rare man who gets to attend his own funeral. It’s an even luckier man who gets to cheat his own death, dust his prints off the murder weapon, read his own eulogy, and rise to live again in another form. That’s what Stephen Colbert did Thursday night with “Stephen Colbert,” in a show that sent his bloviating host character — one of the greatest sustained performances in pop culture, TV or otherwise — off into TV eternity.