Update to 2020b

Revised predictions for Morocco's changes starting in 2023.
Canada's Yukon changes to -07 on 2020-11-01, not 2020-03-08.
Macquarie Island has stayed in sync with Tasmania since 2011.
Casey, Antarctica is at +08 in winter and +11 in summer.
zic no longer supports -y, nor the TYPE field of Rules.