Add a 3rd, optional, parameter to die_error to allow for extended error
information to be output along with what the error was.
Signed-off-by: John 'Warthog9' Hawley <warthog9@kernel.org> Signed-off-by: Jakub Narebski <jnareb@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>