Robert Alexander/Getty ImagesThe Memphis Police Department’s onetime “Officer of the Year” was offered a position with the Nashville PD, which then rescinded the job once the acclaimed cop’s HIV+ status came to light, a new federal lawsuit obtained by The Daily Beast reveals.He helped catch a killer, has been decorated for heroism, and volunteered for one of Memphis’ most challenging assignments. His doctor describes his health as “great,” and says he does not pose “any threat to co-workers or m