Previously the audit list only rendered HH:mm:ss, so a row showing
"21:25:39" gave no hint whether it was today, last week, or last
year. The detail dialog already had the full ISO timestamp, but
the operator had to click each row to find out.
_formatTime now keeps the compact HH:mm:ss form for same-day
events, prefixes MM-dd for older days in the current year, and
shows YYYY-MM-dd for the tail of the log. Always rendered in the
operator's local time zone.
Signed-off-by: flemming-it <stefan.a.flemming@googlemail.com>