Now in trade paperback. Inspector Alan Banks relives the "age of majority" in celebrity crime writer Peter Robinson's 21st and strongest yet book in the internationally celebrated series. For readers of Ian Rankin, Michael Connelly, and Giles Blunt.      A disgraced college lecturer is found murdered with £5,000 in his pocket on a disused railway line near his home. Since being dismissed from his job for sexual misconduct four years previously, he has been living a poverty-st