Happy Sue Gray day. There’s not long left to go now until she submits her inquiry to No. 10, however for those wanting a sneak preview of some of the juicy details expected within, Panorama gave us a teaser last night. Speaking to three anonymous Downing Street Staffers, Laura Kuenssberg heard tales of mass partying, staffers getting intimate, people sleeping overnight in the building, empties being left on desks, bins overflowing with wine bottles, and staffers disrespecting anyone telling them to stop partying. Party politics…