(Editor's note: This story was updated after publication to correct the title of Eric Fanning, acting Air Force secretary.) The White House will tap former Pentagon cost-assessor Christine Fox to temporarily replace outgoing Deputy Defense Secretary Ashton Carter, the Pentagon announced today. Fox, who previously led the Defense Department's cost assessment and evaluation shop and joined the Johns Hopkins University Applied Physics Laboratory as a principal technical adviser in August, has also been working as a consultant to DOD...