PHILADELPHIA — You might think of him first as Lex Luthor or Popeye Doyle or Little Bill Daggett or even as the blind hermit who sets Peter Boyle’s thumb ablaze. But chances are, if you are both a sports fan and a movie buff, when you learned that Gene Hackman had died Wednesday at 95, after an acting career as accomplished and diverse as any in the history of Hollywood, you thought first of one character and one film.