checkout: accord documentation to what git does
checkout: accord documentation to what git does

Signed-off-by: Nicolas Sebrecht <1105e7c0cba85506cc6c81dda1c9e58fcb911a24@gmx.fr>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git