Problem: Compilation of the executable on Windows fails with 'Module
`GHC.IO.Encoding.Iconv' does not export `localeEncodingName'`
Solution: Check if we are on Windows, and don't import such module or
use `localeEncodingName` if it's the case.
* Use `localectl list-locales` if possible.
* Otherwise list `/usr/lib/locale` and try to use `localedef` to list
`/usr/lib/locale/locale-archive`.
* Do not bother with `/usr/share/locale` as, it turns out, it is only used
for localisations by third-party programs on Linux. Strangely, macOS
seems to have actual locale definitions in there, but this tool is
mostly aimed at Linux, since macOS installations are pretty uniform.
