The remote server might not want to tell why it doesn't like us for
security reasons, but let's make the client report such error in a bit
less confusing way. The remote failure remains a mystery, but the local
message might be a bit less so.
[jc: with a gentle wording updates from Andy Parkins]
Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <junkio@cox.net>