[tz] Casey time zone change

[Steffen Thorsen]

Based on information we have received from the Australian Antarctic 
Division, Casey station and Macquarie Island station will move to 
Tasmanian daylight savings time on Sunday 4 October. This will take 
effect from 0001hrs on Sunday 4 October 2020 and will mean Casey and 
Macquarie Island will be on the same time zone as Hobart.

Some past dates too for this 3 hour time change back and forth between 
UTC+8 and UTC+11 for Casey:

- 2018 Oct 7 4:00 - 2019 Mar 17 3:00 - 2019 Oct 6 3:00 - 2020 Mar 8 3:00 
and now - 2020 Oct 4 0:01 Best regards, Steffen - timeanddate.com