Centralize the parsing of the date and time zone strings in the new
helper function show_ident_date() and make sure it checks the pointers
provided by split_ident_line() for NULL before use.
Reported-by: Ivan Lyapunov <dront78@gmail.com>
Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
