`grunt download` fails

[makepanic]

I can't clone this repo and run grunt download as it looks like zdump -v generates timezone lines that the parser is unable to parse.

e.g.

Africa/Abidjan  -9223372036854775808 = NULL
Africa/Abidjan  -9223372036854689408 = NULL
Africa/Abidjan  Mon Jan  1 00:16:07 1912 UT = Sun Dec 31 23:59:59 1911 LMT isdst=0 gmtoff=-968
Africa/Abidjan  Mon Jan  1 00:16:08 1912 UT = Mon Jan  1 00:16:08 1912 GMT isdst=0 gmtoff=0
Africa/Abidjan  9223372036854689407 = NULL
Africa/Abidjan  9223372036854775807 = NULL

It looks like changing zdump -v to zdump -V adjusts its format slightly:

Like -v, except omit the times relative to the extreme time values. This generates output that is easier to compare to that of implementations with different time representations.

This lets download to reach its next error:

zdump can output "UT" for timestamps, which is currently unsupported by the matching regex. One could adjust the regex to make the C optional: UTC?. This allows us to fully compile the timezone data from its IANA sources.

Sadly this causes issues with the test files as all Etc/*.zdump are empty which causes the loader to throw.

I'm not sure what's the best solution to fix this though. I guess one could try to just remove the Etc/* timezones as they're an artifact from ancient times:

These entries are mostly present for historical reasons, so that people in areas not otherwise covered by the tz files could "zic -l" to a timezone that was right for their area. These days, the tz files cover almost all the inhabited world, and the only practical need now for the entries that are not on UTC are for ships at sea that cannot use POSIX TZ settings.

Does anyone know if I'm doing something wrong? I'm using zdump from tzdata 2018i.