[tz] Some time zone history (1)

The Determination of the Time Ordinance, 1919 commenced on 1919-11-24.

Thanks for catching my typo; proposed patch attached and installed into GitHub.

Also, the Defence (Revocation) (No.4) Regulations, 1945 commenced on 1946-01-06.

True, but how would that affect tzdb? As I understand it, those regulations <https://books.google.com/books?id=9as-AQAAIAAJ&pg=PA256> repeal DST, but on 1946-01-06 Gold Coast was already on standard time (having switched from DST on 1946-01-01). Hence on 1946-01-06 there was no clock transition, merely a change in which regulation was in force.