[tz] tzdb timezone names/identifiers and links (was: Add new timezone for Hanoi Capital, Vietnam)

[Guy Harris]

On Feb 19, 2019, at 11:23 AM, Hans-Joerg Happel <happel at audriga.com> wrote:

> Second, what about the case of a Linux laptop located in Hanoi configured to use "Asia/Ho_Chi_Minh". Some sort of calculation might still go wrong then.

...such as converting a POSIX-form date-and-time value from 1972 to local time; it'll use UTC+8 rather than UTC+7, but the latter would be appropriate for local (Hanoi) time in 1972.