builtin/shortlog.c: make usage string consistent with log "--" is used to separate pathspecs from the rev specs, and not rev specs from the options, as the shortlog_usage string currently indicates. In correcting this usage string, make it consistent with the log_usage string. Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>