Detect country of visitor and load default language

[kesar]

Detect country of visitor and load default language if exists in the list.

[tianyangj]

If we need to do IP detection, we probably need an API endpoint with IP to location capability, maybe there are some free 3rd party API available to do this.

However, I feel like using client browser preferred language is probably good enough in our case. We currently doing that in app.components, maybe just need to switch to use TranslateService.getBrowserLang, https://github.com/ngx-translate/core/blob/master/projects/ngx-translate/core/src/lib/translate.service.ts#L487.

[kesar]

good point 👍 we can use browser