Merge branch 'jc/you-still-use-whatchanged'

"git whatchanged" that is longer to type than "git log --raw" which is its modern rough equivalent has outlived its usefulness more than 10 years ago. Plan to deprecate and remove it. * jc/you-still-use-whatchanged: whatschanged: list it in BreakingChanges document whatchanged: remove when built with WITH_BREAKING_CHANGES whatchanged: require --i-still-use-this tests: prepare for a world without whatchanged doc: prepare for a world without whatchanged you-still-use-that??: help deprecating commands for removal