## Updat the tz.js file from https://github.com/darkskyapp/tz-lookup to the package:

tz-lookup is licensed CC0.

Find the latest release (v6.1.8) at https://github.com/darkskyapp/tz-lookup/releases

```
cd inst/tz-lookup
wget -q https://raw.githubusercontent.com/darkskyapp/tz-lookup/v6.1.8/tz.js -O tz.js
```
