bug#34315: [PATCH] icalendar.el: DURATION fix + more robust timezone handling

[Thomas Plass]

Thanks, approved.  Defaulting to local time when decoding seems
reasonable.

Ulf Jasper wrote at 20:05 on September 2, 2020:
: I had to make a small change in the patched version of
: `icalendar--decode-isodatetime' regarding input data in utc zone.