[tz] Please remove tzdata2018f

[Paul Eggert]

On 2/22/19 9:56 AM, Brian Inglis wrote:
> So tzupdater still requires to make or use the rearguard tarball as before.

Actually, I'm seeing reports that it works with the current main-format
tarball.

For what it's worth, I just now tried Oracle's current TZUpdater,
version 2.2.0
<https://www.oracle.com/technetwork/java/javase/tzupdater-readme-136440.html>
dated August, and it didn't error out with the current main-format
tarball (it merely issued warnings). That being said, I lack
installation privileges on the Solaris host I tried this on, and so
didn't check what happens when you use the resulting installation.