#10 showical.perl fails with a component with no attendees

[Mark Tearle]

Running ./showical.perl ../test-data/rfc2445.ics

produces the following error:

EVENTS:

Bastille Day Party (Tue Jul 15 01:00:00 1997)

Attendees
Can't use an undefined value as an ARRAY reference at ./showical.perl line 34.