[tz] Tzdata for Texas

[Paul Eggert]

On 9/12/19 9:06 PM, Ron Sparks wrote:
> I know that Chicago has been the Central Time Zone marker as far back as I
> can remember (at least 1970).

tzdb isn't quite *that* old. That being said, Houston's clocks have agreed with 
Chicago's since 1970 and Chicago is larger than Houston, so Chicago is the 
representative for that timezone. For more about the guidelines, please see:

https://data.iana.org/time-zones/theory.html#naming