debian zoneinfo link fix

[Attila Lendvai]

> I think this would be problematic as symlinks are widely used inside zoneinfo for “aliases”; e.g.

that part of the code only goes through the zone names. later on the
symlinks are resolved when the file contents are needed.

i've recorded my proposed fix that works for me here on debian 8, but
i don't have the commit bit, so see this PR:

https://github.com/dlowe-net/local-time/pull/44

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• attila lendvai
• PGP: 963F 5D5F 45C7 DFCD 0A39
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