Commit 9e64fc9e1c caused a regression
which stored all QDateTime entries as if they were in localtime,
which causes them to be offset by the amount of local timezone
offset. This is fixed by adding "Z" if the time should be in UTC or
using "+/-hh:mm" if it should use fixed UTC offset or specific
timezone.
Task-number: QTBUG-57138
Change-Id: Ie60905dfb3a517db442b636ca41daf8348753d84
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Andy Shaw <andy.shaw@qt.io>
0a5f71c606