Reliable timezone detection using systeminfo for Windows and additional IP Geolocation-based detection. Added a warning message for when auto-detection fails. Fixes #2015.
Cleaner timezone parsing for Linux and add support for Macs
Add portable linux timezone detection for incompatible linux distributions.
Re-use timezone offset parsing
Merge pull request #2151 from sekjun9878/master

Timezone for Windows and IP Geolocation TZdata