Add GeoDB API

[Yizhou150]

Website Description
It exposes city, region, and country data via both GraphQL and REST APIs.

Reason(s) to Support the Website
Collecting countries, cities information

Endpoints
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Questions
Filter cities by name prefix, countries, location, time-zone, and minimum population
Get all country regions, states, and provinces
Get all cities in a given region
Get all countries supporting a currency
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