[tz] Add option to act like global-tz

[Stephen Colebourne]

On Thu, 4 Aug 2022 at 02:28, Paul Eggert <eggert at cs.ucla.edu> wrote:
> On 8/3/22 17:01, Stephen Colebourne via tz wrote:
> > 1) Some of the toolchains (ThreeTen-BP at least) depend on the
> > `leapseconds` file, so can that be added please.
>
> Thanks for pointing that out. I installed the attached patch, which also
> adds the other source files you mentioned. (You also mentioned
> 'backward' which was already included albeit in size-zero form.)

Thanks. I've had a look at the tar.gz file and it now looks like a
"normal" tzdata" file. The only difference is that the data is in one
etcetera file instead of spread out over various continent-like files.

AFAICT, this is sufficient for the Java tooling I'm aware of, although
I've yet to actually run tests on all of them. It does look like
future versions of the Java libraries can use this new option from
tzdb, which is good for everyone concerned.

I'd recommend anyone else that wishes to use a global-tz like
non-merged set of data to try the new tar.gz file to see if it meets
their needs.

thanks
Stephen