Last night the Auditorium Theatre was teeming with opulence and excitement, in addition to Chicago celebrities John Mahoney, Patti LuPone, and Mayor Rahm too. The fancies all gathered to celebrate The Aud’s 125th birthday in the grandest of style, paying homage to the gala opening on Dec 9th, 1889. Orchestral and rock music, opera and broadway, plus representatives from Auditorium’s…