As Sherman’s forces advanced toward the center of Dixie during the summer of 1864, a young woman was compelled to abandon her home and joined a Confederate cavalry unit operating in the woods north of Atlanta. "The Confederate" (2018) draws its story from Lydia Hawke's book “Perfect Disguise,” and it’s a Civil War film made on a small scale, similar to movies like "War Flowers" (2012), "The Last Confederate: The S…